Dissertations / Theses on the topic 'Gamma-aminobutyric acid'
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Robinson, Timothy Neil. "Gamma-aminobutyric acid-mediated neurotransmission in insects." Thesis, University of Bath, 1986. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.760552.
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Aanesen, Arthur. "Gaba and human spermatozoa : characterization and regulation of gaba transport proteins /." Stockholm, 1998. http://diss.kib.ki.se/search/diss.se.cfm?19980925aane.
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Obrocea, Gabriela Valeria. "Ionic mechanisms of anoxia, potential role for gamma-aminobutyric acid." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0027/NQ36789.pdf.
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Wong, Amy NL 1980. "Reduced levels of brain gamma-aminobutyric acid in patients with multiple sclerosis." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=98521.
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Proton magnetic resonance spectroscopy was used to measure relative GABA concentration in the brains of patients with MS. It was hypothesized that microglial activation in MS cortex and presumed associated stripping of GABAergic synapses would be associated with a lowering of GABA concentration.Twelve patients with MS (six relapsing remitting, six secondary progressive) and five healthy control subjects were examined using a GABA-optimized STEAM sequence on a scanner operating at 3.0 tesla. A volume of 2 cm x 3 cm x 3 cm including posterior cingulate and occipital cortex was chosen. GABA/Cr was reduced by approximately 50% in patients with MS with respect to healthy control subjects. This was true for relapsing remitting patients with short duration disease, as well as secondary progressive patients with longstanding disease. NA/Cr, Ino/Cr and GABA/NA were decreased, while Glu/Cr was increased in patients with respect to normal controls.
These observations are consistent with a specific effect of MS on GABAergic interneurons. The fact that this occurs early in the disease suggests that a reduction in GABAergic inhibition may initially be part of a neuroprotective response.
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Dominguez, Jennifer Estrella. "The impact of pregnancy and childbirth on gamma-aminobutyric acid neuronal function." [New Haven, Conn. : s.n.], 2008. http://ymtdl.med.yale.edu/theses/available/etd-12022008-105710/.
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Moore, Melissa Dawn. "The role of the gamma-aminobutyric acid type A receptor in learning and memory." Diss., Restricted to subscribing institutions, 2008. http://proquest.umi.com/pqdweb?did=1779835251&sid=27&Fmt=2&clientId=1564&RQT=309&VName=PQD.
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Lewis, John F. "The design and synthesis of sulphur heterocycles with potential as #gamma#- aminobutyric acid antagonists." Thesis, Staffordshire University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314152.
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Hüser, Anke Christine [Verfasser], and Ulf-Ingo [Gutachter] Flügge. "Gamma-aminobutyric acid Metabolism in Arabidopsis thaliana / Anke Christine Hüser ; Gutachter: Ulf-Ingo Flügge." Köln : Universitäts- und Stadtbibliothek Köln, 2009. http://d-nb.info/116531312X/34.
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Rottkamp, Catherine Anne-Marie. "The role of Hox cofactors in vertebrate spinal coed development." Cleveland, Ohio : Case Western Reserve University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=case1194575822.
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Eroglu, Ezgi. "Association Between Gamma Aminobutyric Acid (gaba) Type B Receptors Gene Polymorphisms And Idiopathic Generalized Epilepsy." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614056/index.pdf.
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Epilepsy is neurological disorder affecting 0.5 to 1% of the population all around the world. It is characterized by the seizures, which are the sudden alterations of behavior due to a temporary change in electrical functioning of the brain. Idiopathic generalized epilepsy (IGE) accounts for one-fifth of all the other epilepsy types, and several gene mutations were identified as the causes of IGE. In general, voltage-gated and ligand-gated ion channel mutations are linked with seizure formation. Gamma amino butyric acid (GABA), the most important inhibitory neurotransmitter of the central nervous system, and its receptors are commonly mentioned in the pathophysiology of epilepsies. Decrease in the inhibitory effect of GABA in neurons causes epileptic discharges resulting in seizure development.
The study population consisted of a total of 176 idiopathic generalized epilepsy (IGE) patients, 83 subjects having psychogenic non-epileptic seizures (PNES), 86 non-epileptic control subjects from Turkey. Total blood samples were obtained from Gülhane Military Medical Academy Hospital Neurology Department, Ankara. There was no statistically difference between the patient and control groups in terms of age. Genomic DNA isolations were performed and genotyping of G1465A and C59T polymorphisms of GABAB1 gene
rs1999501, rs967932, rs3780428 and rs944688 polymorphisms of GABAB2 gene were determined by PCR-RFLP technique. In this study, GABAB1 G1465A polymorphic allele was not observed in Turkish population. For GABAB1 C59T polymorphism, polymorphic allele frequencies were found as 0.097 in IGE patients
0.072 in PNES subjects and 0.105 in non-epileptic control subjects. No significant difference is identified for C59T polymorphism in all three groups. Four SNPs of GABAB2 were studied
rs967932 was found to increase the risk of IGE 3.6-fold (P=0.031) compared to PNES subjects, polymorphic allele frequencies were found as 0.060 in IGE patients
0.018 in PNES subjects and 0.035 in non-epileptic control subjects. For rs1999501 polymorphism, polymorphic allele frequencies were found as 0.077 in IGE patients
0.048 in PNES subjects and 0.093 in non-epileptic control subjects. For rs3780428 polymorphism, polymorphic allele frequencies were found as 0.267 in IGE patients
0.235 in PNES subjects and 0.256 in non-epileptic control subjects. For rs944688 polymorphism, polymorphic allele frequencies were found as 0.196 in IGE patients
0.260 in PNES subjects and 0.227 in non-epileptic control subjects. No significant difference was identified for rs1999501, rs3780428 and rs944688 polymorphisms among IGE patients, PNES subjects and non-epileptic control groups. IGE risk was 6.54-fold higher for subjects having combined GA genotype for rs967932 and GG genotype for rs3780428 when compared with PNES subjects (P=0.042). The combination of CC genotype for rs1999501, GG genotype for rs967932 and TT genotype for rs944688 had around 9-fold protective effect against IGE when both compared with PNES subjects (P=0.038) and non-epileptic control subjects (P=0.041).
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Mistry, Dineshkumar. "The vertebrate neuronal gamma-aminobutyric acid (GABAa) receptor and its modulation : a patch clamp study." Thesis, University of St Andrews, 1988. http://hdl.handle.net/10023/14452.
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Pressure application of gamma-aminobutyric acid (GABA) to mouse spinal and rat DBG neurones maintained in culture evoked transient membrane currents. Using the whole-cell patch clamp technique, these currents were shown to primarily involve the flow of Cl-. The GABA-evoked whole-cell currents in both types of neurones were reversibly suppressed by the GABAA antagonist bicuculline. The barbiturate phenobarbitone reversibly potentiated GABA-evoked whole-cell currents in mouse spinal neurones. Attempts to look at the unitary currents activated by GABA in outside-out patches, revealed spontaneous unitary currents. The I-V relationships of the spontaneous currents were linear and had a reversal potential of OmV in symmetrically distributed Cl solutions. Changing the monovalent cation concentrations on one or both sides of the membrane patch had no effect on the amplitude or the reversal potential of the spontaneous currents. Replacing some of the Cl- in the patch pipette with the impermeant anion SO42- shifted the reversal potential to more negative values. These spontaneous currents in both types of neurones were blocked by bath perfusion of bicuculline. GABA-activated unitary currents in outside-out patches, the main conductance state in both types of neurones was 30pS. However, GABA could occasionally also activate other conductance levels. Spontaneous Cl- currents did not occur in cell-attached patches from mouse spinal and rat DRG neurones, suggesting that the spontaneous events in the outside-out patches did not represent the activity of voltage dependent Cl- channels. Alphaxalone, a steroid anaesthetic, potentiated GABA-evoked whole cell currents in both spinal and DRG neurones. At high (muM) concentrations, pressure application of alphaxalone evoked a membrane Cl- current; this current was reversibly suppressed by blcuculline and potentiated by phenobarbitone. Pregnanolone (5beta-pregnane-3x-ol-20-one) a progesterone metabolite at low (nM) concentrations reversibly enhanced GABA currents in spinal neurones. Pregnanolone at higher concentrations pressure applied to spinal neurones had a weak direct agonist action on the GABAA receptor. Pregnanolone prolonged the burst duration of GABA-activated unitary currents in outside-out patches from spinal neurones. Some of the actions of the steroids on the GABAA receptor were very similar to the barbiturates, bemegride, a respiratory stimulant was formerly used clinically to counteract barbiturate poisoning in man. Experiments were conducted to see whether bemegride could be used as a specific barbiturate antagonist. Bemegride reduced phenobarbitone enhanced GABA currents in mouse spinal neurones. However, bemegride alone also reduced GABA and pentobarbitone evoked currants to a similar extent. This is suggestive of a noncompetitive action on the GABAA receptor, therefore it was not used to elucidate the site of action of steroids.
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Jin, Xiaoming. "Dendritic development of GABAergic cortical interneurons revealed by biolistic transfection with GFP." Morgantown, W. Va. : [West Virginia University Libraries], 2002. http://etd.wvu.edu/templates/showETD.cfm?recnum=2626.
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Thesis (Ph. D.)--West Virginia University, 2002.Title from document title page. Document formatted into pages; contains vii, 218 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references.
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Virmani, M. A. "The effects of ions and drugs on amine and #gamma#-aminobutyric acid release from rat brain." Thesis, University of Newcastle Upon Tyne, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375163.
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Newton, Jonathan. "Temporal Changes in the Levels of Gamma-Aminobutyric Acid in the Brain of the Cockroach, Leucophaea Maderae." TopSCHOLAR®, 1995. http://digitalcommons.wku.edu/theses/917.
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Circadian rhythms have been shown to exist in all studied species and play an important role in their survival. The cockroach is an excellent model organism in which to study circadian systems because of the wealth of background information regarding both its anatomy and circadian system. Clock activity measured electrophysiologically in the cockroach system is 180 degrees out of phase with locomotor activity, with the maximum neural output occurring in the morning, twelve hours prior to the onset of locomotor activity. This inverse relationship of locomotor and neural activity suggests that the clock output may be inhibitory. In vertebrates, the suprachiasmatic nuclei (SCN) is the site of the biological clock, and it has been shown that gamma-aminobutyric acid (GABA) plays an important role in the vertebrate circadian system. The importance of GABA in the vertebrate SCN and its presence in the brain of the cockroach made the inhibitory neurotransmitter GABA a prime candidate for related studies. To determine if GABA was expressed according to a daily rhythm, a brain extract was collected from individual cockroaches at different times of the day and the levels of GABA were determined using HPLC coupled with fluorometric detection. o-Phthalaldehyde was used to make fluorescent derivatives of GABA and the surrogate internal standard, AVA, that could be detected by the system. The levels of GABA determined ranged from 530 ±49 ng/brain at 1800 h, the time when locomotor activity is initiated and neural output from the isolated clock is low (Page 1989), to 793 ± 50 ng/brain at 1200 h, the time of maximum neural output from the clock measured electrophysiologically. These GABA levels and the times at which they occur suggest that the clock may be inhibitory in its action. However, an ANOVA performed on the data did not show a significant difference between the GABA levels at the 95% confidence level, but did at the 84% confidence level (P < 0.162). The sample set was small (n=3 for each time period), and it is possible that with a larger sample set a significant difference at the 95% confidence level could be detected.
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Lau, Wai Kit Jaeger. "Developmental expression of N-methyl-D-aspartate and gamma-aminobutyric acid receptors in the rat basal ganglia." HKBU Institutional Repository, 2004. http://repository.hkbu.edu.hk/etd_ra/535.
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S, Mathew Seena. "Kainate receptor modulation of synaptic transmission in neocortex." Thesis, Birmingham, Ala. : University of Alabama at Birmingham, 2007. https://www.mhsl.uab.edu/dt/2007p/mathew.pdf.
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Howard, MacKenzie A. "Mechanisms of inhibition in the avian cochlear nucleus /." Thesis, Connect to this title online; UW restricted, 2008. http://hdl.handle.net/1773/10551.
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Wells, Jason Eric. "Epileptiform bursting in the disinhibited neonatal cerebral cortex." Morgantown, W. Va. : [West Virginia University Libraries], 2003. http://etd.wvu.edu/templates/showETD.cfm?recnum=3005.
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Thesis (Ph. D.)--West Virginia University, 2003.Title from document title page. Document formatted into pages; contains xii, 231 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references.
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Wingrove, Peter Baxter. "Determinants of ligand selectivity at the benzodiazepine and loreclezole modulatory sites of the #gamma#-aminobutyric acid type A receptor." Thesis, University of Hertfordshire, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302308.
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Saxena, Neeraj. "Investigating the role of Gamma-aminobutyric acid (GABA) in sedation : a combined electrophysiological, haemodynamic and spectroscopic study in humans." Thesis, Cardiff University, 2018. http://orca.cf.ac.uk/111775/.
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A better understanding of the mechanisms of anaesthesia and sedation are expected not only to improve the understanding of the neural correlates of consciousness but also to help improve safety from the complications of anaesthesia/sedation and develop safer drugs and objective brain function monitoring systems. Neuroimaging modalities such as functional MRI, magnetoencephalography and MR spectroscopy provide complimentary information about brain functions and can help interrogate brain activity in a living human brain. Most anaesthetic drugs act by enhancing the inhibitory actions of GABA in the brain. Most neuroimaging research has focused on anaesthetic-induced unconsciousness, with only few investigating the earliest levels of sedation-induced altered consciousness. The work in this thesis used a range of advanced neuroimaging modalities to investigate the role of GABA (through a GABA-ergic drug, propofol), during mild sedation, in humans. This was performed as a series of experiments within two, sequential, scanning sessions, MEG followed by fMRI, in the same participants. Propofol resulted in a dissociation of the visual gamma band response (decreased evoked, increased induced power). This was related to a reduced BOLD fMRI response but there were no changes in MRS detectable GABA concentration. Response to multisensory stimulation also revealed interesting changes with MEG and fMRI. Functional connectivity analyses showed changes in connectivities of the posterior cingulate cortex (key hub of default-mode network) and thalamus with each other and other key brain regions. Resting state networks were identified with MEG too, which revealed interesting increases in connectivity in certain band- limited networks while motor networks showed no change. Perfusion fMRI using arterial spin labelling revealed a global and regional reduction in perfusion, highlighting some of the key regions (frontal cortex, precuenus, PCC and thalamus) involved in sedation.
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Hardy, Steven L. "The role of retrochiasmatic neurons in seasonal breeding in the ewe." Morgantown, W. Va. : [West Virginia University Libraries], 2003. http://etd.wvu.edu/templates/showETD.cfm?recnum=2790.
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Thesis (Ph. D.)--West Virginia University, 2003.Title from document title page. Document formatted into pages; contains vi, 187 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 156-183).
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Aguila, Maria Eliza. "Understanding migraine." Thesis, The University of Sydney, 2017. http://hdl.handle.net/2123/17042.
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Better characterisation of migraine is critical to enhancing its diagnosis, assessment and, ultimately, effective treatments. The aim of this thesis was to better characterise migraine through more detailed investigation of selected headache-related factors and to compare these factors with those seen in other commonly occurring recurrent headaches. The factors investigated in this thesis were neurochemical profile, cervical musculoskeletal impairments, and patient experience, represented by pain and disability characteristics, emotional state and other personal factors. This thesis provides deeper information regarding the nature and characteristics of migraine compared with non-migraine headaches (tension-type and cervicogenic headaches). This thesis has established the potential of GABA as a biomarker for migraine and implies the possible role of GABA in the disease process. This thesis has also characterised migraine according to cervical musculoskeletal impairments and patient experience embodying disability, pain, central sensitisation, and other personal factors. The implications for clinical practice are to assess cervical musculoskeletal impairments and patient experience to facilitate differential diagnosis and prognostication, and to educate patients on the nature of their headaches. Findings from the thesis may also be used by guideline developers, providing stimulus for further discussions on the definition of migraine and reporting of participant selection criteria, with reference to this definition, in clinical trials. Future research directions are identified in validating GABA as a migraine biomarker and elucidating its pathophysiology. By characterising migraine more fully, findings from this thesis will inform the development of effective treatments that could possibly target GABA or clinical characteristics found to be present in migraine. Ultimately this should achieve better health outcomes for people with migraine.
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Salah, Firas Subhi [Verfasser], Iver [Akademischer Betreuer] Petersen, Rolf [Akademischer Betreuer] Bräuer, and Regine [Akademischer Betreuer] Schneider-Stock. "Impact of gamma-aminobutyric acid receptor-associated protein (GABARAP) on carcinogen-induced tumorigenesis / Firas Subhi Salah. Gutachter: Iver Petersen ; Rolf Bräuer ; Regine Schneider-Stock." Jena : Thüringer Universitäts- und Landesbibliothek Jena, 2015. http://d-nb.info/1072072688/34.
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Souza, Sarah Caroline Ribeiro 1986. "Alagamento do sistema radicular em soja : metabolismo de N no nódulo durante o estresse e a capacidade de recuperação." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/315218.
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Orientador: Ladaslav SodekTese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-08-25T05:22:48Z (GMT). No. of bitstreams: 1 Souza_SarahCarolineRibeiro_D.pdf: 2548021 bytes, checksum: 61437f1032c9e4fcc9ee2131a8f6dabe (MD5) Previous issue date: 2014
Resumo: A soja é uma leguminosa amplamente utilizada para estudos envolvendo a fixação biológica de Nitrogênio (N), seja por sua grande importância econômica, seja por sua elaborada e bem sucedida relação simbiótica com rizóbios do gênero Bradyrhizobium, sendo capaz de obter todo N necessário para seu desenvolvimento através da fixação do N2 atmosférico. Todavia, o metabolismo de N em plantas de soja noduladas é sensível à hipóxia provocada pelo alagamento do sistema radicular. Dessa forma, este trabalho teve por objetivo, avaliar os efeitos do alagamento sobre o metabolismo de N em nódulos de soja em diferentes períodos de inundação e recuperação após a drenagem. Para isto, plantas de soja noduladas com o B. elkanii foram submetidas aos experimentos de inundação e recuperação, sendo os períodos de inundação/recuperação variáveis de acordo com o experimento. As alterações no metabolismo foram avaliadas através da análise da composição de aminoácidos por HPLC e avaliação da incorporação de 15N2 nos aminoácidos dos nódulos. Também foi avaliada a atividade da nitrogenase e a expressão dos genes nifH e nifD (nitrogenase), e dos genes que codificam as enzimas glutamato descarboxilase (GAD) e asparagina sintetase (AS) em soja. Verificamos que asparagina (ASN) é o aminoácido mais abundante em nódulos de soja (50%), seguido por glutamato (GLU), serina (SER) e ácido gama-aminobutírico (GABA). Com a inundação observou-se principalmente, uma redução acentuada de ASN, e aumento de GABA, após 4 dias (quando ASN reduziu a quase 1%), além de pequenas alterações na composição de outros aminoácidos. Com os tratamentos de recuperação ASN recuperou-se lentamente e quanto maior o período de exposição ao estresse mais lento o período de recuperação. Aparentemente a redução de ASN nos nódulos foi compensada pelo aumento de GABA. A atividade da nitrogenase foi fortemente inibida pela inundação, mas se recuperou totalmente. Quanto à incorporação de 15N2, verificamos que GLN foi o aminoácido marcado em grau mais elevado, seguido respectivamente por GLU, ASP, ALA e SER. A marcação dos aminoácidos ASN e GABA foi baixa, e isso pode ser devido ao grande "pool" destes aminoácidos no nódulo, ou pela entrada destes aminoácidos a partir de uma fonte não-marcada como o floema. Com relação à inundação, observou-se uma redução na incorporação de 15N2 em ASN, e a recuperação também foi lenta, também houve redução na incorporação em outros aminoácidos como ASP e GLN. A hipóxia afetou a expressão dos genes avaliados nos nódulos. Houve uma redução na expressão dos genes AS1 e AS2, o que condiz com a redução nos teores de ASN. O gene que codifica a GAD também foi menos expresso em nódulos submetidos à inundação o que não explica o aumento de GABA no nódulo durante o estresse. A expressão dos genes nifH e nifD também diminuiram com a inundação, mas se recuperam, e condizem com o observado para atividade da nitrogenase. Dessa forma, verificamos que a inundação afeta o metabolismo de N nos nódulos de soja, em diversos aspectos, como a composição de aminoácidos, atividade da nitrogenase e na expressão de genes envolvidos na assimilação do N em aminoácidos nos nódulos
Abstract: Soybean has been widely used in studies of biological nitrogen fixation, not only because of its economic importance, but in view of its highly efficient symbiotic relationship with rhizobia of the genus Bradyrhizobium, which can supply all the N needed for full development of the plant. However, the process is highly sensitive to oxygen deficiency provoked by waterlogging of the root system, resulting in a rapid and strong inhibition of nitrogen fixation since the availability of oxygen for nitrogenase activity is tightly controlled in the nodule and close to limiting under normal conditions. Thus, this study aimed to evaluate the effects of flooding on the N metabolism in nodules of soybean in different periods of flooding and recovery after drainage. For this, soybean plants nodulated with B. elkanii were subjected to flooding and recovery experiments at stages V7/V8 The flooding/recovery duration was where the flooding/recovery periods were variable according to the experiment. Changes in metabolism were evaluated by analyzing the amino acid composition by HPLC and by assessing the amino acid incorporation of 15N2 of the nodules. Nitrogenase activity and expression of nifH and nifD (nitrogenase) genes, and genes encoding GAD and AS in soybean were also evaluated. The most abundant amino acid in soybean nodules was asparagine (ASN) (50%), followed by glutamate (GLU), serine (SER) and gama-aminobutyric acid (GABA). On flooding, there was a marked decrease of ASN, and increased GABA, mainly after 4 days when ASN dropped to near 1%, as well as smaller alterations in the composition of other amino acids. With the recovery treatments, ASN recovered slowly and the longer the period of exposure to the stress the longer the recovery period. It appears that the reduction of the ASN in nodules is compensated by the increase of GABA. The nitrogenase activity was strongly inhibited by flooding, but full recovery was possible. Regarding the incorporation of 15N2, it was found that GLN is the amino acid labelled to the highest degree, followed respectively by GLU, ASP, ALA and SER. The labelling of the amino acids GABA and ASN was low, which may be due either to the large pool of these amino acids in the nodule, or to the entry of these amino acids from a non-labelled source such as the phloem. Flooding resulted in a reduction of the incorporation of 15N2 in ASN, and recovery was also slow. There was also reduction in the incorporation of 15N2 in other amino acids, such as Asp and GLN. Hypoxia affected the expression of all genes evaluated in nodules. There was a reduction in the expression of the AS1 and AS2 genes, which is consistent with the fall in levels of ASN. Recovery of expression was slow and gradual. Expression of the gene encoding the enzyme GAD was also strongly suppressed in nodules under flooding which does not therefore explain the increase of GABA in the nodule during stress. The expression of nifH and nifD genes were also strongly decreased on flooding, but recovered fully, consistent with the observed data for nitrogenase activity. In conclusion, it was found that flooding affects the metabolism of N in soybean nodules, in diverse ways, such as the amino acid composition, nitrogenase activity, and the expression of genes involved in N assimilation of nodule amino acids
Doutorado
Biologia Vegetal
Doutora em Biologia Vegetal
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Alves, Patricia de Sa e. Benevides Rodrigues. "Interferência da moxidectina na motivação sexual e ereção peniana de ratos: envolvimento de neurotransmissores hipotalâmicos e estriatais." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/47/47135/tde-13062008-100229/.
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A moxidectina (MOX) é um antiparasitário utilizado na clínica veterinária. Em mamíferos seu mecanismo de ação envolve o ácido ?-aminobutírico (GABA), um neurotransmissor que tem papel relevante na regulação dos comportamentos sexual e motor. Dados anteriores por nós obtidos mostraram que a MOX prejudicou o comportamento sexual e a coordenação motora de ratos machos avaliados na trave elevada. Assim, dando continuidade a esse estudo, o objetivo deste trabalho foi avaliar os efeitos da administração da dose terapêutica de MOX (0,2 mg/kg) na motivação sexual e ereção peniana de ratos machos, bem como estudar seu envolvimento em diferentes sistemas de neurotransmissão central. Em todos os experimentos os ratos do grupo experimental receberam a MOX por via subcutânea (SC); e os ratos do grupo controle receberam 1 ml/kg de óleo de amêndoas pela mesma via, e foram avaliados após 72 h. A motivação sexual foi avaliada em um aparelho constituído de uma arena e dois compartimentos separados desta por tela de arame; num compartimento foi colocado um rato macho experiente e no outro uma fêmea sexualmente receptiva. Neste aparelho foi medido o tempo que o rato permaneceu nas proximidades de cada compartimento. Os resultados obtidos neste experimento não mostraram diferenças significantes entre os grupos. A ereção peniana foi induzida pela administração SC de 80 ?g/kg de apomorfina, sendo avaliadas a latência e a freqüência de ereção. Os resultados mostraram aumento da latência e redução da freqüência de ereção peniana dos animais tratados com MOX, enquanto que a administração dos antagonistas GABAérgicos (biculina e faclofen) não alterou estes parâmetros. Por outro lado, observou-se que a biculina (antagonista GABAA) reverteu os efeitos da MOX na ereção peniana, enquanto o faclofen aumentou a freqüência de ereção peniana em ratos tratados com a MOX. Quanto aos níveis hipotalâmicos e estriatais de neurotransmissores e metabólitos, observou-se que a MOX reduziu os níveis estriatais de dopamina e de seu metabólito ácido homovanílico (HVA) e também os níveis hipotalâmicos de GABA. Estes dados sugerem que a MOX embora não interfira na motivação sexual, prejudica o desempenho sexual avaliado pela ereção peniana. Esse efeito da MOX pode ser atribuído a sua ação em receptores GABAA, os quais modulam receptores tipo B, aumentando a liberação de GABA, e 72 h depois, conseqüente redução dos níveis deste neurotransmissor no hipotálamo (uma das áreas centrais envolvidas com o comportamento sexual) e também dos níveis de dopamina e seu metabólito HVA no estriado, área do sistema nervoso central relacionada com a função motora e na qual neurônios GABAérgicos modulam a atividade de neurônios dopaminérgicos.The moxidectina (MOX) is an antiparasitic drug used in veterinary clinic. In mammals its mechanism of action involves GABA, neurotransmitter that has an important role in the regulation of the sexual and motor behaviors. Previous data showed that MOX impair male rat\'s sexual behavior and motor coordination observed at wooden dowel. The objective of the present work was to evaluate the effects of therapeutic dose of MOX (0.2 mg/kg) in sexual motivation and penile erection of male rats, as well as to study its involvement in different central systems of neurotransmission. In all experiments the rats of experimental groups received MOX subcutaneous (SC), and the rats of control groups received 1.0 mL/kg of almonds oil (SC), and were observed after 72h. Sexual motivation test was performed in an arena with two cages, separate from the arena with a wall of wire screen; in one cage was put an intact male rat and in the other one, a sexually receptive female. In this test was measured the time that the rats stayed near of each cage. The data obtained in this experiment didn\'t show any significant differences among the groups. The penile erection (PE) was induced by 80 ?g/kg of Apomorphine (SC), being evaluated the latency to and frequency of PE. The results showed increased latency and reduction of the frequency of PE of animals treated with MOX, while the GABAergic antagonists\' administration (Biculline and Phaclofen) didn\'t change these parameters. On the other hand, it was observed that the Biculline (GABAA antagonist) reversed the effects of MOX in PE, while the Phaclofen increased the frequency of PE in rats treated with MOX. About Hypothalamic and Striatal neurotransmitters levels and their metabolites, was observed that MOX reduced Dopamine (DA) and its metabolite homovanillic acid (HVA) striatal levels and hypothalamic GABA levels. These data suggest that MOX although doesn\'t interfere in sexual motivation, impair sexual performance evaluated by penile erection. This effect of MOX can be attributed to its action in GABAA receptors, which modulate type B receptors, increasing GABA release, and consequent reduction of its levels in the Hypothalamus (one of the central areas involved with sexual behavior) and also, reduction of the DA and its metabolite HVA striatal levels. Striatum is a central nervous system area related with motor function in which GABAergic neurons modulate the activity of dopaminergic neurons.
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Sequerra, Eduardo Bouth. "Express?o de GABA e plasticidade do fen?tipo neuroqu?mico e morfol?gico de c?lulas da Zona Subventricular p?s-natal." Brasil, 2008. https://repositorio.ufrn.br/jspui/handle/123456789/24236.
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A zona subventricular (SVZ) ? um s?tio de cont?nua neurog?nese em mam?feros p?s-natos e adultos. Ao longo de toda a vida, os progenitores neuronais gerados destinam-se ao bulbo olfat?rio (BO) para onde migram atrav?s da via migrat?ria rostral (RMS). Uma vez no BO, os novos neur?nios se diferenciam em neur?nios GABA?rgicos que integram-se ? circuitaria local. A express?o de GABA inicia ainda na zona germinativa. Essa express?o precoce poderia levar a hip?tese de que estes progenitores j? estariam comprometidos com o fen?tipo GABA?rgico. Por?m, para demonstrar seu comprometimento GABA?rgico, um dos passos necess?rios ? mostrar que a descarboxilase do ?cido glut?mico (GAD), a enzima que sintetiza GABA em neur?nios maduros, est? presente nestas c?lulas. Nesta tese mostramos que a express?o e atividade enzim?tica de GAD, s?o muito baixas na SVZ. Revelamos que o GABA presente em neur?nios imaturos da SVZ prov?m de uma via de s?ntese alternativa, a via da putrescina. Para analisar a import?ncia do GABA proveniente de putrescina para estas c?lulas realizamos a inibi??o farmacol?gica de sua s?ntese atrav?s da administra??o de DFMO. Observamos que o tratamento com DFMO regula positivamente a express?o de GAD na SVZ e RMS. Mostramos tamb?m que os neuroblastos da SVZ que expressam GABA s?o realmente pl?sticos quanto a sua escolha de fen?tipo neuroqu?mico. Quando explantes de SVZ s?o co-cultivados com fatias de telenc?falo embrion?rio dorsal, s?tio de gera??o de neur?nios glutamat?rgicos, uma subpopula??o se diferencia em neur?nios GABA?rgicos e outra menor em glutamat?rgicos. Sugerimos, portanto, que a via da putrescina permite que neur?nios imaturos sintetizem GABA sem, no entanto, haver comprometimento com o fen?tipo GABA?rgico. Esta produ??o de GABA parece ser importante para a migra??o de neuroblastos da SVZ, embora n?o tenhamos tido sucesso em mostrar um papel na prolifera??o com o decr?scimo na produ??o do precursor putrescina. Mostramos que a libera??o de GABA de putrescina parece ter um papel em inibir a express?o de GAD nestes neuroblastos. Em contrapartida, a subregula??o desta sinaliza??o levaria ao comprometimento pelo fen?tipo GABA?rgico. Se mudarmos os sinais apresentados ?s c?lulas da SVZ, como ?queles presentes na VZ do telenc?falo embrion?rio, pelo menos uma de suas subpopula??es ? capaz de mudar seu destino fenot?pico, e diferenciar-se em neur?nios glutamat?rgicos piramidais.
The subventricular zone (SVZ) is proliferative epithelium that continuously gives rise to new neurons in postnatal and adult mammals. The neurons generated in the SVZ migrate through the rostral migratory stream (RMS) where they differentiate in GABAergic interneurons. A characteristic of these neuron precursors is that they start to express GABA while they are still in the SVZ. This fact can lead to the conclusion that at this time they are already commited to the GABAergic phenotype. However, to affirm this one has to show that the origin of GABA in these cells is the same as in mature neurons. One of the most important steps to define GABAergic commitment in neurons is to demonstrate the expression of glutamic acid decarboxylase (GAD), the synthetic enzyme for GABA in mature neurons. Here we show that SVZ cells display low levels of GAD immunocytochemistry and enzyme activity as compared with the olfactory bulb. We also show that these cells are able to synthesize GABA using an alternative source, the putrescine pathway. To test the importance of putrescine made GABA in vivo, we pharmacolgically inhibited putrescine synthesis through DFMO administration. We observed that this treatment lead to an increase of GAD expression in the SVZ and RMS. We also show here that SVZ cells can display phenotypic plasticity. Co-culturing SVZ explants and dorsal telencephalic slices, a spot of glutamatergic neurogenesis, we observed that a subpopulation of SVZ derived neurons differentiated into GABAergic neurons and another into glutamatergic pyramidal neurons. Our working hypothesis is that the putrescine pathway is a mechanism to synthesize GABA without commitment to the GABAergic phenotype. The release of putrescine derived GABA inhibits GAD expression leaving these neuroblasts in an undifferentiated state. The inhibition of putrescine synthesis caused an upregulation of GAD expression which would lead to GABAergic commitment. If we present these neuroblasts with different signals, as those present in the embryonic dorsal telencephalon, they would show plasticity in their phenotypic fate and differentiate into other neurochemical and morphological phenotypes, one of which is the glutamatergic pyramidal neuron.
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Greenwood, Jeremy Robert. "Pyridazinediones and amino acid receptors: theoretical studies, design, synthesis, and evaluation of novel analogues." Thesis, The University of Sydney, 1999. http://hdl.handle.net/2123/394.
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http://www.pharmacol.usyd.edu.au/thesis This thesis is primarily concerned with a class of chemical compounds known as pyridazinediones, being 6-membered aromatic rings containing two adjacent nitrogen atoms (pyridazine), doubly substituted with oxygen. In particular, the work focuses on pyridazine-3,6-diones, derivatives of maleic hydrazide (1). Understanding of the chemistry of these compounds is extended, using theoretical and synthetic techniques. This thesis is also concerned with two very important classes of receptors which bind amino acids in the brain: firstly, the inhibitory GABA receptor, which binds g-aminobutyric acid (GABA) (2) in vivo, and for which muscimol (3) is an agonist of the GABAA subclass; secondly, Excitatory Amino Acid (EAA) receptors, which bind glutamate (4) in vivo, and in particular the AMPA subclass, for which (S)-2-amino-3-(3-hydroxy-5-methylisoxazol-4-yl)propionic acid (AMPA) (5) is an agonist. The connection between pyridazinediones and amino acid receptors is the design, synthesis, and evaluation of structures based on pyridazinediones as potential GABA and EAA receptor ligands. Techniques of theoretical chemistry, molecular modelling, synthetic chemistry, and in vitro pharmacology are used to explore pyridazine-3,6-dione derivatives as ligands.
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Greenwood, Jeremy Robert. "Pyridazinediones and amino acid receptors: theoretical studies, design, synthesis, and evaluation of novel analogues." University of Sydney, Department of Pharmacology, 1999. http://hdl.handle.net/2123/394.
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http://www.pharmacol.usyd.edu.au/thesis This thesis is primarily concerned with a class of chemical compounds known as pyridazinediones, being 6-membered aromatic rings containing two adjacent nitrogen atoms (pyridazine), doubly substituted with oxygen. In particular, the work focuses on pyridazine-3,6-diones, derivatives of maleic hydrazide (1). Understanding of the chemistry of these compounds is extended, using theoretical and synthetic techniques. This thesis is also concerned with two very important classes of receptors which bind amino acids in the brain: firstly, the inhibitory GABA receptor, which binds g-aminobutyric acid (GABA) (2) in vivo, and for which muscimol (3) is an agonist of the GABAA subclass; secondly, Excitatory Amino Acid (EAA) receptors, which bind glutamate (4) in vivo, and in particular the AMPA subclass, for which (S)-2-amino-3-(3-hydroxy-5-methylisoxazol-4-yl)propionic acid (AMPA) (5) is an agonist. The connection between pyridazinediones and amino acid receptors is the design, synthesis, and evaluation of structures based on pyridazinediones as potential GABA and EAA receptor ligands. Techniques of theoretical chemistry, molecular modelling, synthetic chemistry, and in vitro pharmacology are used to explore pyridazine-3,6-dione derivatives as ligands.
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Rahman, Mozibur. "Effects of neuroactive steroids on the recombinant GABAA receptor in Xenopus oocyte." Doctoral thesis, Umeå : Univ, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1112.
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Karlsson, Urban. "GABA-, glycine- and glutamate-induced currents in rat medial preoptic neurons : functional interactions and modulation by capsaicin." Doctoral thesis, Umeå : Univ, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1383.
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McDonald, Emily F. "Expression of GABA receptors in human sclera." Thesis, Queensland University of Technology, 2014. https://eprints.qut.edu.au/68604/2/Emily_McDonald_Thesis.pdf.
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Alves, Patricia de Sá e. Benevides Rodrigues. "Efeitos da moxidectina no comportamento sexual de ratos machos." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/47/47135/tde-29062006-183245/.
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A moxidectina é uma droga antiparasitária, do grupo das milbemicinas, utilizada em animais domésticos. Em mamíferos seu mecanismo de ação envolve o GABA, neurotansmissor que tem um papel relevante na regulação do comportamento sexual. Assim, o presente trabalho estudou os efeitos da moxidectina no comportamento sexual de ratos machos. Uma vez que alterações na função motora podem interferir na manifestação deste comportamento, avaliou-se, inicialmente, a atividade geral no campo aberto e a coordenação motora na trave elevada, e posteriormente, o comportamento sexual de ratos inexperientes e experientes. A avaliação da atividade geral dos ratos observados no campo aberto mostrou que, mesmo em altas doses (2,0 e 20,0mg/kg), a moxidectina não altera o comportamento de ratos no campo aberto. Esta droga, porém, prejudicou a coordenação motora dos animais avaliados na trave elevada, sendo este efeito atribuído, ao menos em parte, à ação da moxidectina em receptores GABAérgicos. Os resultados obtidos na avaliação do comportamento sexual de ratos inexperientes mostraram redução da motivação sexual dos animais que receberam 0,2mg/kg de moxidectina e foram observados 24 ou 72horas depois. Nenhuma alteração significante foi observada nos diferentes parâmetros do comportamento sexual dos ratos experientes, indicando que a experiência sexual pode reverter os efeitos desta droga. Estes resultados mostraram que a moxidectina prejudicou o comportamento sexual de ratos machos inexperientes e a coordenação motora, efeitos estes atribuídos a uma ação central desta droga em receptores GABAA.The moxidectin is an antiparasitic drug that is used in domestic animals. It is a semi-synthetic milbemycin. Its mechanism of action, in mammals, involves GABA, neurotransmiter that has an important role in the regulation of the sexual behavior. Thus, the present work studied the effects of the moxidectin in male rats sexual behavior. Due to the fact that alterations in the motor function can interfere in the expression of this behavior, it was evaluated, initially, the general activity in the open field and the motor coordination at wooden dowel, and later, the sexual behavior of naïve and experienced rats. The evaluation of the general activity of the rat observed in the open field showed that, even in high doses (2.0 and 20.0 mg/kg), the moxidectin do not alter the behavior of the rats in open field. However, this drug was able to impair the motor coordination of the animals at the wooden dowel. As a matter of fact, this effect is due, at least part of it, to the action of the moxidectin in GABAergics receptors. The results achieved in the evaluation of naïve male rats sexual behavior showed reduction of the sexual motivation of the animals that received 0.2 mg/kg of moxidectin and were observed after 24 or 72 hours later. No significant alteration was detected in the various parameters of the experienced rats sexual behavior, indicating that the sexual experience could revert the effects of this drug. The moxidectin impair the sexual behavior of naive male rats and the motor coordination, and the reasons that caused these effects were attributed to a central action of the moxidectin at GABAA receptors.
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Pimentel, Neusa Maria Nascimento. "Avaliação da resposta imuno-inflamatória no tecido cerebral de camundongos deficientes em CRAMP submetidos a modelo de etilismo agudo." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/5/5164/tde-28092018-092046/.
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O uso de álcool está aumentando em nossa sociedade e permanece associado a inúmeros problemas sociais, econômicos e de saúde. De fato, o álcool e os problemas de saúde associados a ele exercem um impacto importante na prática médica e representam um dos maiores desafios da saúde pública. O consumo de álcool na sociedade contemporânea é geralmente aceito positivamente, dificultando o reconhecimento de certos padrões de consumo como doença. O alcoolismo é um transtorno recidivante crônico caracterizado pela ingestão compulsiva de quantidades excessivas de etanol, perda de controle em sua ingestão, comportamento inadequado e a presença de um estado emocional negativo. O consumo de quantidades nocivas de álcool resulta em danos físicos e psicológicos e o vicio é um transtorno psiquiátrico que afeta as funções executivas, causando perda de interesse em outros alvos do prazer e comportamento compulsivo de busca por drogas. O álcool interage com vários sistemas neurológicos. O presente trabalho analisou a resposta imunoinflamatória no tecido cerebral de camundongos CRAMP knockout (KO) jovens e tipo selvagem (WT) submetidos ao modelo de intoxicação alcoólica, com o objetivo de investigar o impacto de CRAMP na dependência alcoólica no adolescente. O CRAMP é um peptídeo antimicrobiano com efeitos pleotrópicos e, até onde sabemos, seu papel nunca foi investigado nesse sentido. Também analisamos a secreção de vários neuropeptídeos, proteínas e citocinas. Nossos resultados mostraram uma diferença significativa na ingestão de etanol entre os animais comparados CRAMP KO e WT, o que foi relacionado a um aumento nos níveis cerebelares de IL-1beta. Concluimos que os pepitídeos antimicrobianos podem ter um papel importante na resposta imunoinflamatória que ocorre durante o etilismo agudoThe use of alcohol is increasing in our society and remains associated with countless social, economic and health problems. In fact, alcohol and the health issues associated to its abuse exert an important impact on medical practice and represent one of the biggest challenges of public health. The consumption of alcohol in contemporary society is generally accepted positively, making certain patterns of consumption very difficult to be recognized as a disease. Alcoholism is a chronic relapsing disorder characterized by compulsive ingestion of excessive amounts of ethanol, loss of control in its intake, inappropriated behavior and the presence of a negative emotional state. The consumption of harmful amounts of alcohol results in physical and or psychological damage and addiction is a psychiatric disorder that affects the executive functions, causing loss of interest in other aspects of life and a compulsive behavior. Alcohol interacts with several neurologic systems. The present work analyzed the immuno-inflammatory response in the brain tissue of young CRAMP knockout (KO) and wild-type (WT) mice submitted to a model of alcohol intoxication, in order to investigate the impact of CRAMP in teenager alcohol addiction. CRAMP is an antimicrobial peptide with pleotropic effects and, as far as we know, its role had never been investigation in this regard. We also analysed the secretion of several neuropeptides, proteins and cytokines. Our results showed a significant difference in ethanol intake when CRAMP KO and WT animals were compared, which was related to an increase in the cerebellar levels of IL-1beta. We conclude that antimicrobial peptides may play an important role in the immunoinflammatory response that occurs during acute alcoholism
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Vieira, Domingos Sávio de Souza [UNIFESP]. "Fisiopatologia da cefaléia crônica diária: estudo do líquido cefalorraquidiano." Universidade Federal de São Paulo (UNIFESP), 2008. http://repositorio.unifesp.br/handle/11600/9654.
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Publico-10777.pdf: 584483 bytes, checksum: e11ab9839fe48602b080e48c338291cc (MD5)Introdução: A cefaléia crônica diária é constituída por um grupo de cefaléias, dentre elas a enxaqueca crônica, comórbida com patologias como a depressão, o abuso de medicamentos, a obesidade e, mais recentemente, associada a casos de hipertensão intracraniana idiopática sem edema de papila. Objetivos: Determinar a prevalência de hipertensão intracraniana idiopática sem edema de papila e os níveis liquóricos de glutamato e ácido gama-aminobutírico em pacientes com enxaqueca crônica comparado a outros grupos de pacientes. Métodos: Foram estudados pacientes com enxaqueca crônica, mediante a realização do exame do líquido cefalorraquidiano com medida da pressão de abertura e dosagens dos níveis liquóricos dos aminoácidos glutamato e ácido gama-aminobutírico pela técnica de cromatografia líquida de alta resolução. Resultados: Dos pacientes submetidos a punção lombar, seis pacientes, em grupo de sessenta, tiveram elevação na pressão liquórica maior que 200 mm H20 sem acusar edema de papila à fundoscopia. Os pacientes que abusavam de triptanos mostraram níveis liquóricos de glutamato menores que aqueles com uso abusivo de outros tipos de medicações analgésicas e pacientes que não abusavam de nenhum tipo de medicação. Quanto aos níveis de ácido gamaaminobutírico no líquido cefalorraquidiano, esses foram menores nos pacientes com enxaqueca crônica e depressão quando comparados aos pacientes que tinham apenas enxaqueca crônica. Conclusões: A realização do estudo do líquido cefalorraquidiano foi importante em pacientes com enxaqueca crônica para a exclusão da hipertensão intracraniana idiopática sem papiledema, possibilitando perspectivas futuras para o entendimento da fisiopatogênese e desenvolvimento de novas terapias medicamentosas para a enxaqueca e suas comorbidades.
Introduction: Chronic daily headaches consist of a group of headaches, among them chronic migraine, that is comorbid with depression, overuse of medication, obesity and recently, cases of idiopathic intracranial hypertension without papilloedema. Objectives: To establish idiopathic intracranial hypertension without papilloedema prevalence and glutamate and gamma-aminobutyric acid levels in cerebrospinal fluid from patients with chronic migraine compared to other groups of patients. Methods: We studied patients with chronic migraine, who underwent lumbar puncture to rule out idiopathic intracranial hypertension without papilloedema. Amino acids glutamate and gamma-aminobutyric acid levels were measured by high performance liquid chromatography in cerebrospinal fluid. Results: Six patients, among sixty, had CSF open pressure higher than 200 mm H20 without papilloedema on fundoscopy. Patients who overused triptans had glutamate levels lower than those with abuse of other analgesic types and nonoverusers. The gamma-aminobutyric acid levels in cerebrospinal fluid were lower in depressed patients when compared to patients without depression and controls. Conclusions: The study of the cerebrospinal fluid was important in patients with chronic migraine for the exclusion of idiopathic intracranial hypertension without papilloedema, opening perspectives for the understanding of the physiopathology and development of new drug therapies for migraine and its comorbidities.
TEDE
BV UNIFESP: Teses e dissertações
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Faroni, Alessandro. "Expression of GABA receptors in stem cell derived Schwann cells and their role in the peripheral nervous system." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/expression-of-gaba-receptors-in-stem-cell-derived-schwann-cells-and-their-role-in-the-peripheral-nervous-system(5ca8d27c-cfdb-4db7-82fc-44575ca41539).html.
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Peripheral nerve injuries occur with high incidence and often result in profound and permanent impact on the life of patients and on healthcare expenditure. Schwann cells (SC) play a promoting role in peripheral nerve regeneration providing physical and neurotrophic support that aids axon re-growth. However, these beneficial properties are not exploitable in nerve tissue engineering due to the difficulties in SC harvesting and expansion in culture. Adult stem cells derived from bone marrow (BM-MSC) and from adipose tissue (ASC) can be differentiated in SC-like cells and be used as SC substitutes in bioengineered nerve conduits for the improvement of peripheral nerve regeneration. Pharmacological intervention approaches for the treatment of nerve injury are still not clinically available. Nevertheless, γ-Aminobutyric acid (GABA) receptors have been recently suggested as a putative target for such purpose. GABA is the main inhibitory neurotransmitter of the adult brain and interacts with two different receptor types. However, both GABA-A and GABA-B receptor types are functionally expressed also in SC, where they are involved in the regulation of SC physiology and in the development of the peripheral nervous system (PNS).The aim of this thesis was to characterise the GABAergic system of BM-MSC and ASC differentiated into a SC-like phenotype and to evaluate changes in the expression levels following differentiation. Moreover, the effect of specific GABA receptor ligands on cell proliferation and neurotrophic potential of differentiated stem cells were assessed. Using reverse transcriptase polymerase chain reaction, western blot analysis and immunohistochemistry we demonstrated that adult stem cells express several subunits of both GABA-A and GABA-B receptor systems such as GABA-B1a, GABA-B1b and GABA-B2, as well as GABA-A α2 and GABA-A β3. Expression levels and cellular localisation were comparable with adult and neonatal SC cultures used as positive controls, and protein expression levels for some of the subunits changed following glial differentiation. Interestingly, stimulation of GABA receptors with specific agonists influenced stem cell proliferation in two opposite ways. Baclofen, a GABA-B receptor agonist decreased proliferation of SC and differentiated ASC (dASC), but not of SC-like BM-MSC (dBM-MSC). By contrast, muscimol, a GABA-A receptor agonist, increased proliferation in SC and in both dASC and dBM-MSC. This suggests that GABAergic signalling could be a potential player in the mechanisms regulating stem cell differentiation and proliferation as reported in SC. Finally, baclofen treatments on SC and dASC modulated the expression levels and the release of the neurotrophins BDNF and NGF, which are key actors in the processes involved with peripheral nerve regeneration. Although further studies will be needed to clarify the role of GABA receptors in the PNS, the presence of functional GABA receptors on SC-like adult stem cells could represent an exploitable pharmacological target to modulate stem cell physiology and improve their neurotrophic potential for peripheral nerve regeneration.
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Malinina, Evgenya. "Neurotransmission and functional synaptic plasticity in the rat medial preoptic nucleus." Doctoral thesis, Umeå : Umeå university, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-25874.
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Lasham, Annette. "The structure and expression of #gamma#-aminobutyric acidâ†A (GABAâ†A) receptor subunit genes." Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.259594.
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Oshima, Toshiyuki [Verfasser], and Rainer [Akademischer Betreuer] Schmelzeisen. "Effect of gamma-aminobutyric acid lactam (GBP-L) in combination with mesenchymal stem cells (MSCs) and bovine bone mineral (BBM)on bone formation and osseointegration of dental Implants in maxillary sinus augmentation = Der Einfluß von Gabapentin-Laktam in Kombination mit mesenchymalen Stammzellen und bovinem Knochenersatzmaterial auf die Knocheneubildung und Osseointegration von Zahnimplantaten bei Sinusbodenaugmentation." Freiburg : Universität, 2013. http://d-nb.info/1123477906/34.
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Diana, Pérez Marina. "Desarrollo de un pan de masa madre rico en GABA y péptidos IECA." Doctoral thesis, Universitat de Barcelona, 2014. http://hdl.handle.net/10803/284604.
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Existe una relación evidente entre el consumo de sal y el mayor riesgo de padecer hipertensión. La hipertensión es una enfermedad crónica que afecta a algo más del 40% de la población general adulta en España. El pan es uno de los alimentos básicos de la dieta humana siendo en España la principal fuente dietética de sodio en la población adulta. El uso de masa madre produce un pan con una notable mejora de las características nutricionales y sensoriales, incluyendo aroma, sabor, textura de la corteza y miga, así como un alargamiento de la vida útil del pan. En este contexto nace el proyecto de obtener una nueva formulación de pan de masa madre funcionalmente activo, contribuyendo a disponer de un alimento saludable con propiedades beneficiosas para la salud. Para ello, se ha estudiado la posibilidad de sustituir el sodio (Na) por potasio (K) en las formulaciones de pan y la inclusión de moléculas biológicamente activas con un efecto hipotensor científicamente demostrado. El Ácido γ-Amino Butírico (GABA), un amino ácido no proteico, con numerosas funciones fisiológicas entre los que se encuentra el sistema de regulación de la presión arterial. La ingesta de un alimento rico en GABA y una reducción de su contenido en sal pueden ayudar a reducir la tensión arterial. En el proyecto se reúnen por tanto, las dos condiciones básicas para la obtención de un pan, elaborado con una masa madre que realza el sabor del pan, enmascarando posibles defectos asociados a la inclusión de sal potásica y por otra parte, la posibilidad de que esta masa madre contenga además sustancias bioactivas como el GABA y los Inhibidores del Enzima Convertidor de la Angiotensina (IECA).
En el primer estudio se aislaron bacterias ácido lácticas de quesos artesanales españoles con el fin de obtener cepas altamente productoras de GABA. Las cepas fueron sometidas a ensayos cualitativos y ensayos cuantitativos para evaluar la habilidad de sintetizar GABA. Tras la selección de la mejor cepa, Lactobacillus brevis CECT 8183, ésta se usó para la producción de una masa madre optimizada para la producción de GABA. Los ensayos se llevaron a cabo a escala laboratorio y a escala piloto. En el estudio II se analizó el contenido de aminoácidos libres de los quesos artesanales con especial interés en conocer el perfil de GABA y ornitina como posibles compuestos bioactivos en los quesos y encontrar relación entre la capacidad de producción de la cepa aislada y el contenido de GABA presente en el queso. En el tercer estudio se obtuvo un pan elaborado con la masa madre rica en GABA que fue comparado con otros panes del mercado en cuanto contenido de aminoácidos, aminas biógenas y acrilamida como principales compuestos derivados del nitrógeno. Finalmente, se hizo una revisión del GABA como molécula bioactiva con gran interés aplicativo en la industria alimentaria. Estos resultados pueden contribuir a mejorar los beneficios para la salud de los panes enriquecidos en GABA y a tener en cuenta la cepa Lactobacillus brevis CECT 8183 como estárter para la producción de alimentos ricos en GABA.The use of dough containing naturally occurring lactobacilli and yeasts produces bread with a notable improvement in nutritional and sensorial characteristics, including the aroma, taste and texture of both the crust and the crumb, and also increases the useful life of the bread. From this stems the project to obtain a new bread formulation using such a dough that is functionally active and contributes to providing a healthy foodstuff with beneficial properties. To this end we studied the possibility of substituting the sodium (Na) by potassium (K) in bread formulations and the inclusion of biologically active molecules with a scientifically demonstrated hypotensive effect. γ-Aminobutyric acid (GABA) is a non-protein amino acid with numerous physiological functions including playing a role in the regulation of blood pressure. Intake of food rich in GABA and a reduction in its salt content may help reduce blood pressure. Therefore, this project brings together two basic conditions for the production of a bread made using dough containing naturally occurring lactobacilli and yeasts which heightens the taste of the bread and furthermore offers the possibility that this dough also contains bioactive substances such as GABA and angiotensin-converting-enzyme (ACE) inhibitors. In the first study lactic acid bacteria were isolated from Spanish artisanal cheeses in order to obtain strains that produce large amounts of GABA. The strains were subjected to qualitative and quantitative tests to evaluate their capacity to synthesise GABA. After selection of the best strain, Lactobacillus brevis CECT 8183, it was used to produce a dough optimised for the production of GABA. In another study a bread was produced with the experimental dough, rich in GABA, and it was compared with other commercially available breads in terms of amino acid, biogenic amine and acrylamide contents as the main nitrogen-derived compounds. These results could contribute to improving the health benefits of breads enriched in GABA and to raising awareness of the strain Lactobacillus brevis CECT 8183 as a starter ingredient for the production of foodstuffs rich in GABA.
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Espinoza, María Janina Carrera, and 尹珍妮. "A study of gamma– Aminobutyric acid production by Lactobacillus spp." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/4d56ph.
Full textAbstract:
碩士元智大學
生物科技與工程研究所
106
Gamma-aminobutyric acid (GABA) is a four carbon non-protein amino acid that is widely distributed in nature; it is an important bioactive regulator, and it is considered a major inhibitory neurotransmitter of the vertebrate central nervous system. As a metabolic product of microorganisms produced by the decarboxylation of glutamic acid. A wide range of traditional foods produced by microbial fermentation contain GABA, in which GABA is safe and eco-friendly, and also has the option of providing new health-benefited foods enriched with GABA. GABA’s biosynthesis is primarily through the α-decarboxylation of glutamate by glutamate decarboxylase (GAD), therefore the optimal fermentation condition is mainly based on the biochemical properties of the enzyme. Previous studies have shown that the major GABA production by microbial fermentation is produced by lactic acid bacteria (LAB) that has proven effective as a food additive; this microorganism has the ability to grow and act like probiotics in the gastrointestinal tract. The main factors that can affect GABA production by microbial fermentation include temperature, pH, fermentation time, agitation rate, and carbon sources. This research aimed to investigate the effects of culture conditions mentioned above on GABA production by Lactobacillus brevis and Lactobacillus plantarum. The results showed that GABA production yield was 420 mg/L (48 h at 30oC, pH 5.0 and 150 rpm) by Lb. brevis, and 295 mg/L (48 h at 37oC, pH 5.0 and 0 rpm) by Lb. plantarum. To increase the production yield using a precursor like Monosodium Glutamate (MSG) as a catalyst and the addition of glucose the results showed gamma-aminobutyric acid production was 478 mg/L by Lb. brevis (2% MSG/ 1% Glucose) and 415 mg/L by Lb. plantarum (4% MSG/4%Glucose) after that we tested fermentation time (range 6 hours) and inoculum percentage the final results showed an increase in GABA production (486 mg/L and 481 mg/L) by Lb. plantarum (4%MSG, 4% glucose, 0rpm. 5.0 pH, 24h, 4% inoculum) and Lb. brevis (2%MSG, 4% glucose, 0rpm. 5.0 pH, 30h, 4% inoculum) respectively. Keywords: Gamma-aminobutyric acid (GABA), culture conditions, carbon sources, lactic acid bacteria, microbial fermentation, Monosodium glutamate (MSG), Lactobacillus brevis, Lactobacillus plantarum.
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Rozycki, Michelle. "Dietary Oligosaccharides Modulate Bifidobacterial Production of the Neurotransmitter Gamma-Aminobutyric Acid." 2020. https://scholarworks.umass.edu/masters_theses_2/989.
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Bifidobacteria are the predominant members of the infant gut, colonize adults to a lesser extent, and are recognized as beneficial microbes. Various bifidobacterial species produce ��-aminobutryic acid (GABA), the chief inhibitory neurotransmitter in the mammalian central nervous system. It is postulated that in order to produce GABA, the bifidobacterial genome must contain the gadB and gadC genes which encode a glutamate decarboxylase and a glutamate/GABA antiporter, respectively. Once exported by GadC, GABA is absorbed and transported systemically throughout the host. We hypothesize that specific dietary oligosaccharides will modulate bifidobacterial production of GABA due to varying intracellular concentrations of glutamate. To test this, 33 bifidobacterial strains were screened for GABA production via reverse phase HPLC. Interestingly, 10 strains contained both gadB and gadC genes, but only 8 strains produced detectable GABA in vitro. To further elucidate the extrinsic factors influencing GABA production, strains were subjected to different dietary components. Specifically, lactose and the dietary oligosaccharide FOS were evaluated for the ability to promote biosynthesis of intracellular glutamate and thus potentially GABA. Understanding the relationship between diet, bifidobacterial physiology, and GABA production may inform dietary interventions to modulate this neurotransmitter in vivo.
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Chou, Hao, and 周浩. "A study of gamma– Aminobutyric acid production by recombinant Escherichia coli." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/68537792599675841414.
Full textAbstract:
碩士元智大學
生物科技與工程研究所
104
In recent years, depression, lack of sleep, nervous, patients with hypertension and other diseases increase, and high blood pressure caused by cerebrovascular disease is the decade has been one of the top ten causes of death of our people. However, functional foods in recent years improved dramatically in the Taiwan market, also functional foods market about 1,250 billion dollars in 2016. Gamma-aminobutyric acid (GABA) is a four carbon non-protein amino acid widely used in pharmaceutical field and food industry. It has been used as a bioactive component due to its potential in controlling neurotransmitter signal and lowering blood pressure in human. GABA is a natural metabolic intermediate by various microorganisms, such as bacteria, yeasts, and fungi. The biosynthesis of GABA is one step reaction of decarboxylating glutamate to GABA by glutamate decarboxylase (GAD; EC: 4.1.1.15). Glutamate decarboxylase is considered responsible for GABA production in GABA-producing strain. In this study, exploit recombinant DNA technology will be able to Glutamate decarboxylase (GAD) is an enzyme that catalyzes the decarboxylation of glutamate to GABA cloning to the plasmid established a production system for GABA from recombinant Escherichia coli DH5α/pBAD33-gadA. According the results, we have already successfully gadA gene cloning to the plasmid pBAD33.The apparent molecular mass of GAD was estimated as 52 kDa by the SDS-PAGE analysis. And the use of high performance liquid chromatography (HPLC) for analysis GABA production of recombinant bacteria. To improve production yield of glutamate decarboxylase with recombinant E. coli, the concentration of inducer (L-arabinose), glutamic acid, glucose, PLP, the induction time, medium compositions and culture conditions were investigated. The results shows that E. coli DH5α/ pBAD33-gadA using M9 medium (0.3% disodium hydrogen phosphate and 0.5% yeast extract)with 0.5% glutamic acid , 1% glucose , 10 mM arabionse, 0.02 mM PLP and 40℃and pH 6.5 for 22h could obtain 235 mg/l GABA prodution.
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Jezyk, Nancy. "The intestinal transport of gamma-aminobutyric acid derivatives in the rat." 1998. http://catalog.hathitrust.org/api/volumes/oclc/68800245.html.
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Song, Hung-Yi, and 宋鴻宜. "Development of gamma-aminobutyric acid-enriched functional fermented milk from adzuki beans." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/m2ykcs.
Full textAbstract:
博士國立臺灣大學
食品科技研究所
105
Gamma-aminobutyric acid (GABA) is a non-protein amino acid widely distributed in nature, and is a major inhibitory neurotransmitter in the central nervous which provides several physiological functions. Development of functional foods rich in GABA through microbial fermentation has a potential in the consumer market. This study was used the domestic adzuki beans(Vigna angularis) variety Kaohsiung No.8 that produced from Wandan Township as the material to evaluate the effect of different pretreatment conditions on the GABA accumulation, and further inoculate different probiotics in the adzuki bean milk to select the suitable probiotic strain for GABA production. This study also adjusts the optimum conditions for the culture media and develops functional fermented adzuki bean milk that carries both the GABA and probiotics. The GABA content in raw adzuki beans was 6.81 mg/100g DW. After soaking at 37℃ for 8 hours, the GABA content in the adzuki beans increased to 90.21 mg/100g DW, which was 13-fold higher than non-treated adzuki beans. The total phenolic acid content was increased from 14.85mg GAE/g DW to 18.04mg GAE/g DW, the soaking treatment was not favorable to stabilization of the anthocyanins that the content of anthocyanins was decreased. The GABA content of adzuki bean freezing at -20℃ for 48 hours and thawing at room temperature for 48 hours after soaking at 37℃ for 8 hours was increased 70% higher than that of un-freezing beans. The anthocyanin and total phenolic content of adzuki beans after freezing and thawing treatment was decreased 47% and 51% respectively, which indicated that the effect of freezing and unfreezing treatment after soaking treatment on raising the content of GABA was limited. The adzuki beans was added 5 folds water and soaked at 37℃ for 8 hours, homogenized into thick liquid and added 5％ skimmed milk powder to make adzuki bean milk. Adzuki bean milk inoculated with Lactobacillus rhamnosus GG increased GABA content from 0.05 mg/mL to 0.44 mg/mL after 36 hours of fermentation, which showed the greatest elevation in this study. The anthocyanin content was increased 2.88-fold and the total phenolic content was increased 40％ than un-fermented adzuki bean milk. Further, the optimal cultural condition to adzuki bean milk inoculated with Lb. rhamnosus GG to improve the GABA content by response surface methodology (RSM). The results showed that GABA content was dependent on the addition of galactose, monosodium glutamate and pyridoxine with which the increasing ratios of GABA was 23~38％, 24~68％, and 8~36%, respectively. The optimal culture condition for GABA production of adzuki bean milk was addition of galactose 1.44%, monosodium glutamate 2.27%, and pyridoxine 0.20%. Under the optimal cultural condition, the GABA content of fermented adzuki bean milk was 1.12 mg/ml, increased 22.4 folds higher than that of the unfermented adzuki bean milk. The acid-sugar ratio of fermented adzuki bean milk was adjusted to 16 by sensory evaluation had higher score on sweetness, acidity and overall acceptance of the fermented adzuki bean milk. After 15 days of storage at 4℃, the GABA content of fermented adzuki bean milk was remained 1.26 mg/ml and the lactic acid bacteria number was maintained at log 9.42 cfu/ml. The fermented adzuki bean milk was contained both in GABA and probiotic that suitble for consumers as a daily supplement as suggested.
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Zhang, HaiGuang. "The structural basis of pharmacological sensitivity in the Drosophila [gamma]-aminobutyric acid receptor." 1996. http://catalog.hathitrust.org/api/volumes/oclc/35671174.html.
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Liu, Bai-Chia, and 劉百嘉. "Effects of gamma-aminobutyric acid on commensal microbiota and intestinal immunity in VHL knockout mice." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/8m27k5.
Full textAbstract:
碩士國立臺灣大學
生化科技學系
106
The prevalence of end-stage renal disease in Taiwan is the highest worldwide. Studies have demonstrated that kidney disease is related to imbalance of intestinal immunity and gut microbiota products. GABA is an inhibitory neurotransmitter and suggested great potential for immune-modulatory and anti-inflammatory agents. However, the effects of GABA on intestine is not clear. VHL conditional knockout mice (Vhlhdel/del) in C57BL/6J background spontaneously developed renal inflammation have been studied for renoprotective effects of GABA in our Lab. Therefore, this study is to investigate whether GABA could affect commensal microbiota and intestinal immunity in murine renal injury. Firstly, Vhlhdel/+ mice fed with aristolochic acid (AA) to induce acute kidney injury. Eleven to thirteen-week-old Vhlhdel/+ male mice were fed with AIN-93 diet (Con and AA groups), or GABA containing diets (Gr-AA and G-AA groups). After two weeks, AA (4 mg/kg BW/day) was added in three AA groups for the other two weeks. The results showed that GABA significantly decreased urine protein, serum creatinine and BUN levels. The Gr-AA group increased cecal Lactobacillus. The G-AA group increased the population of cecal Bifidobacterium, and had the highest cell numbers of regulatory T (Treg) cells in Peyer’s patch (PP). Both Gr-AA and G-AA groups increased IL-10 secretion in ConA-stimulated PP cells. These results implied that GABA supplements increased gut beneficial symbionts and regulatory cytokine secretion in AA-induced Vhlhdel/+ AKI mice. Secondly, Vhlhdel/del mice which spontaneously develope renal inflammation and renal carcinoma were used as chronic kidney disease model. Five-week-old weaning Vhlhdel/del mice fed with AIN-93 diet (Con group), or GABA containing diet (Gr and G groups) for ten weeks, and then sacrificed. The results showed that GABA significantly reduced the level of Kim-1 in urine. The Gr group increased the IL-10 secretion in ConA-stimulated mesenteric lymph nodes (MLN) cells, but TNF-α secretion decreased. The G group increased cecal Lactobacillus, decreased the population of Treg cells in both PP and MLN, and the population of CD103+ dendritic cells in lamina propria. Meanwhile, cytokines IL-10 and TGF-β produced by ConA-stimulated PP cells and TNF-α, IL-6 and IL-10 produced by ConA-stimulated MLN cells were decreased. These results indicated that GABA rice promotes regulatory immune response, but GABA pure compound inhibits regulatory immune response in gut. In conclusion, intake of GABA rice or GABA pure compound could affect the intestinal microbiota and intestinal immune responses which might be beneficial for delaying the progress of renal disease in VHL knockout mice.
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Jabang, Sona, and 蘇娜. "Primary recovery of Gamma-aminobutyric acid from cell culture using the aqueous two-phase system." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/7xk7k7.
Full textAbstract:
碩士元智大學
生物科技與工程研究所
106
Aqueous biphasic system, liquid-liquid fractionating technique, is usually formed as a result of mutual incompatibility of two polymers, solvents or one polymer and a salt above a critical concentration. Owing to its great potentials in the extraction, separation, purification, enrichment of proteins, viruses, enzymes, nucleic acid and other biomolecules made it extensively used in both industry and academic field. Hence, this simple and scalable technique was employed in the present study to recover a valuable compound, Gamma-aminobutyric acid (GABA). The GABA, a non-proteinous amino acid, is the principal inhibitory neurotransmitter in the central nervous system of mammalian. It is ubiquitous in vertebrates, and in microbes and insects as a metabolite. The physiological functions of GABA have been felt on victims suffering from tranquillizers, anxiety, depression, Alzheimer, Schizophrenia, diabetes and hormonal imbalance, medically. Pharmaceutically, drugs are invented to enhance the availability of GABA. Besides, it serves as the major building block for the synthesis of 2-pyrrolidone and biodegradable polyamide nylon 4 making it boost the interest of the industrial field. GABA is biologically synthesized from the principal excitatory neurotransmitter, L glutamate, by glutamate decarboxylase in the presence of pyridoxal 5’ phosphate. The increasing demand of GABA has prompted scientist to elucidate the efficient production of GABA. However, separation remains in the challenging manner. To this end, polyethylene glycol of different molecular weight (2000, 4000, 6000 and 8000) /dipotassium hydrogen phosphate and potassium dihydrogen phosphate (K2HPO4 and KH2PO4) at different physiological pH was utilized for the construction of binodal curve and tie lines. In the case of alcohol-salt base, ethanol/methanol and dipotassium hydrogen phosphate/tri sodium citrate and ammonium sulfate were used for the phase diagram construction. Separation of GABA was done using High-Performance Liquid Chromatography. The derivatization was completed with 1, fluoro 2,4 dinitrobenzene (FDNB). During the phase formation, methanol/tri sodium citrate could not form two phases due to the heavy salting out effect. Although, salting out effect was observed in ethanol/ammonium phase formation, yet phase formation was successful. Equally, polyethylene glycol and phosphates have been good phase formers, thus, binodal curve and tie lines construction were made possible. Since ABS is hindered by many factors. Therefore, the parameters such as volume ratio, molecular weight, temperature, physiological pH, salt effect, centrifugal force and shaking, were evaluated. The optimal conditions investigated for the salt was 0.5 M NaCl at ambient temperature. The salt effect of the ammonium chloride and sodium chloride on the separation had a significant different at p < .05. The physiological pH investigated were possible with only alkaline condition and 7.5 was the optimal pH evaluated. Also, the centrifugal force and shaking maximal conditions were 1500 and 50 rpm respectively. The separation of gamma aminobutyric acid from crude cell with the optimal conditions was archived with the Lactobacillus brevis. At an initial concentration of 482 mg/L, the percentage yield obtained was 99%. The different biomass loading of GABA producing bacteria show an increasing partition coefficient with increasing yield 108% when higher biomass was loaded. This elucidates the effect of biomass loading amount favours the partitioning of the GABA in the top phase, meaning, GABA can be separated and purified with this method. Also, the recovery of gamma aminobutyric acid at the final concentration of L. brevis (14000 mg/L), had an actual yield of over 88%. The assimilation from yeast, presents a percentage yield of 78% from the different GABA stock concentration 0f 40% (w/v). The extraction efficiency was 0.95 and the purity attained was 100%. ATPS has been proven to be a promising tool for the recovery of GABA. Keywords: Aqueous-two phase, Gamma-aminobutyric acid, Polyethylene glycol, Derivatization neurotransmitter, 2-pyrrolidone, glutamate decarboxylase
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Trotter, Stacey Ann. "Development and dysfunction of GABAergic synaptic function in a seizure-prone animal model of cortical malformation /." 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:3225944.
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Hsu, Ching-Yu, and 許瀞尤. "Composition of gamma-aminobutyric acid, phenolic acids and bioactivities of black soybean koji fermented with Monascus pilosus BCRC 31526." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/24047596044349271165.
Full textAbstract:
碩士國立臺灣大學
食品科技研究所
102
In this study, a solid fermentation was performed on black soybeans with Monascus pilosus BCRC 31526 at 30℃ for a period up to 10 days. The functional components including phenolic acids, γ-aminobutyric acid (GABA) and amino nitrogen of black soybean koji were examined. The change of glutamate decarboxylase activity was also investigated. Inhibitory effect of methanol extracts of fermented or non-fermented black soybean on the production of NO and TNF-α in the LPS-induced macrophages were also compared. It was found that the 10 day-fermented black soybean contained the highest amount of phenolic acids which is ca 2.04 times that of the unfermented black soybean. Content of GABA was found closely related to the glutamate decarboxylase activity noted in the fermented black soybean. They all increased as the fermentation was extended and reached their maxima after 6 days of fermentation. Further extension of fermentation resulted in the reduction of GABA content and glutamate decarbosylase activity. Fermentation was also found to enhance the amino nitrogen content of black soybean. Methanol extracts of the fermented or non-fermented black soybean at a dosage of 15 ug/mL showed inhibitory effect on the production of NO and TNF-α in the LPS-induced macrophages. Furthermore, the inhibitory effect exerted by the fermented black soybean extract was generally significant higher (p<0.05) than that of the non-fermented black soybean extract.
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Tang, Chia-Wei, and 唐嘉偉. "Production of fermented milk with gamma-aminobutyric acid (GABA) by lactic acid bacteria and evaluation of lactic acid bacteria of probiotic potential property." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/7v3j2j.
Full textAbstract:
碩士國立臺灣海洋大學
食品科學系
102
gamma-Aminobutyric acid (GABA) is a well-known non-protein amino acid, which is widely distributed in animals and plants. GABA has been reported to be a major inhibitory neurotransmitter in the mammalian central nervous system and show antihypertensive activity. This aims of this research are to manufacture a GABA-enriched fermented milk by lactic acid bacteria (LAB) isolated from fish intestines and to evaluate the probiotic potential property of the GABA-producing LAB. Preliminarily, lactic acid bacteria strains were isolated from healthy fish intestine from previous study. Ten lactic acid bacteria strains of 126 LAB strains were screened based on the capacity of synthesizing GABA. And ten GABA-producing strains show that none of them exhibited hemolytic activity. Moreover, five strains exhibited partial bile salt hydrolase activity, including the strain FPS 2520. FPS 2520 also showed a high percentage of adhesion to monolayer of Caco-2 cells. Strain FPS 2520 demonstrated high survival viability to gastrointestinal conditions simulating stomach and duodenum passage. Optimal conditions of strain FPS 2520 for producing GABA in whole milk were: 10% reconstituted whole milk, initial inoculum size of 5 log CFU/mL, addition of 20 mM MSG, 1% brown sugar, and 0.5% yeast extract during fermentation at 37oC for 48 hours. The results indicated FPS 2520 show a probiotic potential property and have a great application in milk fermentation for the production of G (10.67 mg/mL), and the IC50 of ACEI-inhibitory activity is 0.28 ± 0.02 mg/mL. Besides lactic acid bacteria number slightly decreased, pH value, titratable acidity and GABA concentration didn’t have significant difference compare to control at 4oC for 14 days. Using mixed strains, GABA-producing strain FPS 2520 and proteinase-positive FKR 3737 could significantly enhance the GABA production about 14.74 mg/mL.