Acid In Brain Tissue Research Articles

High proline levels in the brains of mice as related to specific learning deficits

Hyperprolinemic PRO/Re mice have been studied as potential models for hyperprolinemia in man. In addition to high proline levels, some heretofore unreported amino acid abnormalities in the brains of PRO/Re mice are described. The T-maze and shuttlebox learning abilities of PRO/Re mice were compared with those of CD-1 mice having normal proline levels. PRO/Re mice had a significant deficit for T-maze learning, but a significantly greater aptitude for shuttlebox learning when compared to CD-1 mice. By studying the F3 progency of the PRO/Re × CD-1 cross, these strain-specific differences in learning ability for different tasks were shown to be unrelated to the differences in brain proline levels. F3 mice could be subdivided into two distinct groups: those with high proline (HP+) and low proline (HP−) titers. Other amino acids in brain tissues were essentially identical in both groups. A comparison of learning abilities of these HP+ mice with their HP− littermates showed no meaningful differences. However, the slightly slower rate at which HP+ mice acquired shuttlebox learning was sufficiently consistent over the 8 day training period so that it became significant. These results do not support the hypothesis that high levels of proline in brain tissues and blood are necessarily accompanied by impaired learning and memory, but are in agreement with those studies of hyperprolinemia in man that suggest no consistent learning deficits in hyperprolinemic subjects. The results seem to validate the suitability of the PRO/Re mouse as a model for hyperprolinemia in man. The data suggest also that the altered amino acid pattern in brains of PRO/Re mice has multiple etiologies. The possibility remains that in PRO/Re mice, the differences in ability to learn the T-maze and shuttlebox are the result of the interaction of high proline levels with some of the other biochemical abnormalities in the brain tissues of this mouse strain.

Comparison of high-performance liquid chromatography and gas chromatography-mass spectrometry for the analysis of indole-3-acetic acid in brain tissue

Comparison of high-performance liquid chromatography and gas chromatography-mass spectrometry for the analysis of indole-3-acetic acid in brain tissue

Flow injection analysis with an enzyme reactor bed for determination of ascorbic acid in brain tissue.

L'emploi d'un reacteur a ascorbate oxydase immobilisee sur Sepharose associe a un detecteur electrochimique, permet le dosage rapide de l'acide ascorbique du tissu cerebral en presence des catecholamines et de leurs metabolites

Simultaneous multiple electrode liquid chromatographic—electrochemical assay for catecholamines, indoleamines and metabolites in brain tissue

To enhance the selectivity of liquid chromatographic—electrochemical assays for biogenic amines and metabolites in brain tissue, multiple electrode transducers were investigated. Two configurations of dual working electrodes were examined: parallel—adjacent and series arrangements. Using the raw detector currents with each configuration, peak-height ratios from simultaneously generated chromatograms were calculated to assess the selectivity of the instrument for direct injections of brain tissue supernatant. Ratios were consistent with injections of standards. Nearly coeluting peaks such as norepinephrine and 3-methoxy-4-hydroxyphenylglycol were resolved by using dual detector electrodes in series; only the catecholamines were detected at the downstream electrode owing to their electrochemical reversibility. The scheme was applicable to the assay of norepinephrine, 3,4-dihydroxyphenylacetic acid, dopamine, homovanillic acid, serotonin, 5-hydroxytryptophan and 5-hydroxyindole-3-acetic acid in brain tissue in less than 15 min.

Disaggregation of polyribosomes and depletion of amino acids in brain tissue after a single injection of amino acid in young rats

Journal of Inherited Metabolic DiseaseVolume 5, Issue S1 p. 2-2 Short Communication Disaggregation of polyribosomes and depletion of amino acids in brain tissue after a single injection of amino acid in young rats Kikumaro Aoki, Kikumaro Aoki Research Development Department, Aiiku Maternal and Child Health Center, 5-6-8 Minami Azabu, Minato-Ku, Tokyo, 106 JapanSearch for more papers by this author Kikumaro Aoki, Kikumaro Aoki Research Development Department, Aiiku Maternal and Child Health Center, 5-6-8 Minami Azabu, Minato-Ku, Tokyo, 106 JapanSearch for more papers by this author First published: 01 March 1982 https://doi.org/10.1007/BF01799798AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume5, IssueS1March 1982Pages 2-2 RelatedInformation

A Comparison Of Measurement of Homovanillic Acid in Brain Tissue by Gas Chromatography Mass Spectrometry and Liquid Chromatography with Electrochemical Detection

Abstract A comparison of liquid chromatography with electrochemical detection (LCEC) and gas chromatography mass spectrometry (GCMS) has been made for analysis of homovanillic acid (HVA) in rat brain tissue. The LCEC procedure gave slightly higher average values of HVA in the samples measured; however, the HVA content determined by both methods related significantly. Rat brain meostriatum was used as representative samples for comparison of the two analytical procedures.

Simultaneous determination of catecholamines and unconjugated 3,4-dihydroxyphenylacetic acid in brain tissue by ion-pairing reverse-phase high-performance liquid chromatography with electrochemical detection

A rapid, sensitive method was developed for the simultaneous assay of catecholamines and 3,4-dihydroxyphenylacetic acid in rat brain tissue. The method is simple, involving only tissue disruption, adsorption of the catechols onto alumina, desorption, and injection into a reverse-phase high-performance liquid chromatography system. Selectivity and high sensitivity are obtained using electrochemical detection. The addition of 3,4-dihydroxyphenylacetic acid determination to assays for catecholamines allows one to observe effects of pharmacological maniqulations on in vivo monoamine oxidase activity and/or turnover of dopamine as well as effects on catecholamine concentrations.

Severe hypoglycemia leads to accumulation of arachidonic acid in brain tissue.

It is now well known that brain tissues only contain a small pool of free fatty acid (FFA), of which the polyenoic arachidonic and docosahexanoic acids comprise a minor part (see Bazan 1976, Marion & Wolfe 1979). This pool increases rapidly in ischemia and, under those circumstances, the polyenoic acids form the major part of the pool. Accordingly, it has been concluded that ischemia preferentially activates phospholipase A2.

I. Liquid chromatography with pre-column sample enrichment and electrochemical detection. Regional determination of serotonin and 5-hydroxyindoleacetic acid in brain tissue

A highly selective and sensitive method for the measurement of serotonin and its metabolites in brain tissue has been developed, based on reverse-phase liquid chromatography. The method combines a clean-up step on small, gravity-fed isolation columns with a liquid chromatograph utilizing an on-line sample enrichment procedure. This procedure significantly increases the sensitivity available, allowing determination of picomolar concentrations. Application of this technology is made to the determination of serotonin (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) in cerebrospinal fluid and small regions of the mammalian brain. As little as 1 mg. of tissue can be studied with a RSD of 4.46% for 5-HT and 5.98% for 5-HIAA.

Effect of administration of 5-hydroxytryptophan and an inhibitor ofl-aromatic amino acid decarboxylase on glucose metabolism in rat brain

The effect of 5-hydroxytryptophan (5-HTP)--the precursor of serotonin (5-hydroxytryptamine, 5-HT)--and of an inhibitor, N-(DL-seryl)-N'-(2,3,4-trihydroxybenzyl)hydrazine (Ro4-4602), of L-aromatic amino acid decarboxylase on the metabolism of glucose to amino acids in brain tissue was investigated. Labeled glucose (20 muCi, 0.24 mg in 0.2 ml 0.9% saline) was injected intravenously into fed rats pretreated with Ro4-4602 (50 mg/kg intraperitoneally) either alone or in combination with 5-HTP (30 mg/kg intravenously) or with the appropriate vehicle. After the injection of Ro4-4602 plus 5-HTP, the concentrations of 5-HT and 5-HTP in brain were increased, but the increase of 5-HTP was more pronounced and prolonged than the increase in 5-HT. This suggested that Ro4-4602 slightly inhibits the reaction of decarboxylation in the brain, although at the dose used the drug is usually considered to act only peripherally. After administration of Ro4-4602 alone or combined with 5-HTP, the concentration of glucose in plasma was not significantly increased. However, the concentration of glucose in brain was markedly increased with such treatments. The administration of Ro4-4602 alone or combined with 5-HTP reduced the flux of 14C from labeled glucose to amino acids in brain. The concentrations of amino acids in brain were little changed by these treatments.

Rapid method for the assay of 4-aminobutyric acid (GABA), glutamic acid and aspartic acid in brain tissue and subcellular fractions

The thin-layer electrophoretic separation at pH 4.8 of brain extracts and a procedure for fluorescent staining of the plates with fluorescamine are described for the rapid routine determination of 4-aminobutyric acid (GABA), glutamic acid and aspartic acid in brain extracts and in particulate fractions of brain tissue. Automated sample application, electrophoretic separation using two chambers, and quantitation by in situ fluorescence scanning allows the assay of 280 samples within three working days. The method is reproducible (S.D. less than 8% of the mean) within the range of 0.2--2 nmole per spot. The staining procedure can be applied to a variety of related analytical problems. The method has proved useful for the determination of the specific radioactivities of GABA, glutamic acid and aspartic acid in metabolic studies.

Mass fragmentographic determination of 5-hydroxytryptamine and 5-hydroxyindole-3-acetic acid in brain tissue using deuterated internal standards

A mass fragmentographic method for the determination of 5-hydroxytryptamine (5-HT) and 5-hydroxyindole-3-acetic acid (5-HIAA) in the same extract of rat brain tissue is described. Deuterium-labelled analogues were used as internal standards. 5-HT and 5-HIAA were separated by solvent extraction and pentafluoropropionyl derivatives were prepared for the mass fragmentographic analysis. Multiple ion analysis confirmed the identity of 5-HT and 5-HIAA in the rat brain. At the mass numbers used routinely for the determination of 5-HT and 5-HIAA, the experimental error was below 3% (calculated from mean values of 0.50 and 0.24 nmole, respectively). The recovery of the authentic compounds added to brain extracts was more than 95%. The levels of 5-HT and 5-HIAA in the rat brain were 2.95 ± 0.16 and 0.64 ± 0.18 nmole/g, respectively. More than 100 samples could be analyzed within 3 days. The presence of 5-hydroxytryptophol in rat brain was also investigated, but none could be detected either as a conjugate or as the free alcohol.

Simultaneous mass fragmentographic determination of 3, 4-dihydroxyphenylacetic acid and 4 hydroxy-3-methoxyphenylacetic acid in brain tissue.

A massfragmentographic method for determination of 3, 4-dihydroxyphenylacetic acid (DOPAC) is described. Deuterium labelled DOPAC was used as internal standard. Derivatives suitable for GC-MS were prepared by reacting standard solutions and rat brain extracts with pentafluoropropanol and pentafluoropropionic anhydride. Fragments set into focus were m/e 592/597 (M+) and m/e 415/420 (M+ −177). The sensitivity was in the pmole range with high specificity as tested by multiple ion analysis. The DOPAC level in rat striatum was 6.0 ± 1.1 nmoles/g with an experimental error below 8.5%. The recovery of 575 pmoles DOPAC added to brain extracts was 91 %. Treatment of rats with pargyline (150 mg/kg i.p.) reduced the DOPAC level by about 95% whereas a slight elevation was obtained after administration of chlorpromazine (10 mg/kg i.p.). DOPAC and 4-hydroxy-3-methoxyphenylacetic acid (HVA) could be determined concomitantly in the same sample, by using the described technique for derivative preparation and an AVA allowing simultaneous recording of 4 mass numbers.

Simultaneous microdetermination of homovanillic acid and 5-hydroxyindoleacetic acid in brain tissue using Sephadex G-10 and QAE-Sephadex A-25

Homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) in animal brains were simultaneously purified by two steps of column chromatography on Sephadex G-10 and QAE-Sephadex A-25. Perchloric acid extracts of brain tissue were directly passed through a column of Sephadex G-10. The gel retained both HVA and 5-HIAA, thereby separating them from Cl0 − 4 which interferes with subsequent purification process and from endogenous substances which give blank fluorescence. HVA was loosely adsorbed on the gel and was easily desorbed with dilute acetic acid. This effluent was successively passed onto a column of QAE-Sephadex A-25 placed beneath the G-10 column and the adsorbed HVA was eluted with 0.1 M Na 2HPO 4. The 5-HIAA remaining on the Sephadex G-10 without being desorbed by acetic acid was eluted with dilute ammonia. The recovery of both acid metabolites by this column procedure was more than 90%. Thus, it is possible to determine the levels of HVA and 5-HIAA in single brains of small rodents.

Content of N-acetyl-1-aspartic acid in brain tissue after head injuries

Content of N-acetyl-1-aspartic acid in brain tissue after head injuries

The effect of stereoisomers of cycloserine on the formation and transformation of free ?-aminobutyric acid in brain tissue

A study was made of the effect produced by the stereoisomers of cycloserine on decarboxylization of glutamic acid and transamination of γ-aminobutyric acid with α-ketoglutaric acid in the homogenates of the rat brain at pH 7.5. As revealed. D.L-cycloserine in a concentration of 10−3 M depressed the first process by 40% and the second one by 45%. In the same conditions D-cycloserine depressed glutamic acid decarboxylation by 9%; it somewhat activated γ-aminobutyric acid transamination. A discussion is presented on the possible effect of cycloserine isomers on the content of free γ-aminobutyric acid in the brain (in vivo) following the administration of isoniazid in large doses.

The determination of gamma-aminobutyric acid in brain

A simple method for the determination of γ-aminobutyric acid in brain tissue is described. Two columns of ion-exchange resin are used. An extract of rat brain is first passed through Amberlite CG-50, which removes basic amino acids and amines. The effluent from this column is then passed through a column of Dowex 50 buffered at pH 3.1. Elution from this column with pH 3.1 buffer removes other interfering amino acids from the resin. Good recoveries of GABA added alone, in a mixture of amino acids, or mixed with a true brain extract were obtained. Values of the GABA content of brain obtained by this method agree well with those reported in the literature.

Participation of the ammonium ion in the transformation of glucose to amino acids in brain tissue.

The brain slices were incubated with uniformly 14 C labelled glucose and ammonium nitrate labelled with 15 N in the ammonium nitrogen for 60 min at 37 °C. It was shown that ammonia was readily incorporated by the brain slices into glutamine, glutamic acid and aspartic acid, but only to a small extent into γ -aminobutyric acid, glycine and alanine. The significance of the low incorporation of labelled nitrogen into γ -aminobutyric acid with respect to the high specific activity in glutamic acid is discussed.

On Sialic Acid in Brain Tissue.

On Sialic Acid in Brain Tissue.

AMMONIA FORMATION AND GLUTAMIG ACID IN BRAIN TISSUE

Journal Article AMMONIA FORMATION AND GLUTAMIG ACID IN BRAIN TISSUE Get access GENKICHIRO TAKAGAKI GENKICHIRO TAKAGAKI Department of Physiology, School of Medicine, Keio UniversityTokyo Search for other works by this author on: Oxford Academic PubMed Google Scholar The Journal of Biochemistry, Volume 42, Issue 2, March 1955, Pages 131–139, https://doi.org/10.1093/oxfordjournals.jbchem.a126515 Published: 01 March 1955 Article history Received: 18 December 1954 Published: 01 March 1955