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Veech RL, Harris RL, Mehlman MA. Brain metabolite concentrations and redox states in rats fed diets containing 1,3-butanediol and ethanol. Toxicol Appl Pharmacol 1974; 29:196-203. [PMID: 4283684 DOI: 10.1016/0041-008x(74)90056-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- R L Veech
- National Institute of Mental Health, Saint Elizabeth's Hospital, Washington, D.C
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Patel MS, Tonkonow BL. Development of lipogenesis in rat brain cortex: the differential incorporation of glucose and acetate into brain lipids in vitro. J Neurochem 1974; 23:309-13. [PMID: 4153857 DOI: 10.1111/j.1471-4159.1974.tb04359.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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54
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Simler S, Owsianowski N, Randrianarisoa H, Ledig M, Mandel P. Biosynthesis of free amino acids in the brain of Jimpy mice. J Neurochem 1974; 23:359-63. [PMID: 4154095 DOI: 10.1111/j.1471-4159.1974.tb04366.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Shank RP, Baxter CF. Metabolism of glucose, amino acids, and some related metabolites in the brain of toads (Bufo boreas) adapted to fresh water or hyperosmotic environments. J Neurochem 1973; 21:301-13. [PMID: 4724320 DOI: 10.1111/j.1471-4159.1973.tb04251.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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58
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Hawkins RA, Miller AL, Nielsen RC, Veech RL. The acute action of ammonia on rat brain metabolism in vivo. Biochem J 1973; 134:1001-8. [PMID: 4762748 PMCID: PMC1177908 DOI: 10.1042/bj1341001] [Citation(s) in RCA: 219] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
1. Acute NH(4) (+) toxicity was studied by using a new apparatus that removes and freezes the brains of conscious rats within 1s. 2. Brains were removed and frozen 5min after intraperitoneal injection of ammonium acetate (2-3min before the onset of convulsions). Arterial [NH(4) (+)] rose from less than 0.01 to 1.74mm at 4-5min. The concentrations of all glycolytic intermediates measured, except glucose 6-phosphate, were increased by the indicated percentage above the control value as follows: glucose (by 41%), fructose 1,6-diphosphate (by 133%), dihydroxyacetone phosphate (by 164%), alpha-glycerophosphate (by 45%), phosphoenolpyruvate (by 67%) and pyruvate (by 26%). 4. Citrate and alpha-oxoglutarate concentrations were unchanged and that of malate was increased (by 17%). 5. Adenine nucleotides and P(i) concentrations were unchanged but the concentration of creatine phosphate decreased slightly (by 6%). 6. Brain [NH(4) (+)] increased from 0.2 to 1.53mm. Net glutamine synthesis occurred at an average rate of 0.33mumol/min per g. 7. The rate of brain glucose utilization was measured in vivo as 0.62mumol/min per g in controls and 0.81mumol/min per g after NH(4) (+) injection. 8. The arteriovenous difference of glucose and O(2) increased by 35%. 9. No significant arteriovenous differences of glutamate or glutamine were detected. Thus, although much NH(4) (+) was incorporated into glutamine the latter was not rapidly released from the brain to the circulation. 10. Plasma [K(+)] increased from 3.3 to 5.4mm. 11. The results indicate that NH(4) (+) stimulates oxidative metabolism but does not interfere with brain energy balance. The increased rate of oxidative metabolism could not be accounted for only on the basis of glutamine synthesis. We suggest that increased extracellular [NH(4) (+)] and [K(+)] decreased the resting transmembrane potential and stimulated Na(+),K(+)-stimulated adenosine triphosphatase activity thus accounting for the increased metabolic rate.
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DeVivo DC, Leckie MP, Agrawal HC. The differential incorporation of beta-hydroxybutyrate and glucose into brain glutamate in the newborn rat. Brain Res 1973; 55:485-90. [PMID: 4736603 DOI: 10.1016/0006-8993(73)90319-3] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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60
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Hindfelt B. The effect of acute hypocapnia upon the energy state of the brain in sustained hyperammonemia. Scand J Clin Lab Invest 1973; 31:399-408. [PMID: 4761788 DOI: 10.3109/00365517309084324] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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61
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Hindfelt B. The effect of acute ammonia intoxication upon the brain energy state in rats pretreated with L-methionine D-L-sulphoximine. Scand J Clin Lab Invest 1973; 31:289-99. [PMID: 4755033 DOI: 10.3109/00365517309082433] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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62
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Shimada M, Kihara T, Kurimoto K, Watanabe M. Incorporation of 14 C from (U- 14 C)glucose into free amino acids in mouse brain loci in vivo under normal conditions. J Neurochem 1973; 20:1337-44. [PMID: 4716828 DOI: 10.1111/j.1471-4159.1973.tb00245.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Weyne J, Van Leuven F, Leusen I. Glutamate and glutamine in the brain: influence of acute pCo 2 changes in normal rats and in rats under sustained hypercapnia or hypocapnia. LIFE SCIENCES. PT. 2: BIOCHEMISTRY, GENERAL AND MOLECULAR BIOLOGY 1973; 12:211-8. [PMID: 4695841 DOI: 10.1016/0024-3205(73)90349-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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65
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Hindfelt B. The effect of sustained hyperammonemia upon the metabolic state of the brain. Scand J Clin Lab Invest 1972; 30:245-55. [PMID: 4640633 DOI: 10.3109/00365517209084286] [Citation(s) in RCA: 37] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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66
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Veloso D, Passonneau JV, Veech RL. The effects of intoxicating doses of ethanol upon intermediary metabolism in rat brain. J Neurochem 1972; 19:2679-86. [PMID: 4673618 DOI: 10.1111/j.1471-4159.1972.tb01327.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Van Gelder NM, Sherwin AL, Rasmussen T. Amino acid content of epileptogenic human brain: focal versus surrounding regions. Brain Res 1972; 40:385-93. [PMID: 4623783 DOI: 10.1016/0006-8993(72)90141-2] [Citation(s) in RCA: 226] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Gaitonde MK, Kelly R. Compartmentation and labelling of amino acids in the developing rat brain after injection of (U- 14 C) ribose. J Neurochem 1972; 19:377-88. [PMID: 5010083 DOI: 10.1111/j.1471-4159.1972.tb01347.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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69
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Lolley RN. Changes in glucose and energy metabolism in Vivo in developing retinae from visually-competent (DBA-1J) and mutant (C3H-HeJ) mice. J Neurochem 1972; 19:175-85. [PMID: 5009894 DOI: 10.1111/j.1471-4159.1972.tb01267.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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70
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Johnson JA, Fusaro RM. The role of the skin in carbohydrate metabolism. ADVANCES IN METABOLIC DISORDERS 1972; 60:1-55. [PMID: 4581900 DOI: 10.1016/b978-0-12-027306-5.50006-1] [Citation(s) in RCA: 43] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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71
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Strang RH, Bachelard HS. Effect of insulin on levels and turnover of intermediates of brain carbohydrate metabolism in vivo. J Neurochem 1971; 18:1799-807. [PMID: 5118334 DOI: 10.1111/j.1471-4159.1971.tb09585.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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van den Berg CJ, Garfinkel D. A simulation study of brain compartments. Metabolism of glutamate and related substances in mouse brain. Biochem J 1971; 123:211-8. [PMID: 5164952 PMCID: PMC1176925 DOI: 10.1042/bj1230211] [Citation(s) in RCA: 344] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
A computer model of the metabolism of glutamate, glutamine, gamma-aminobutyrate, and the tricarboxylic acid cycle in mouse brain has been constructed in terms of 39 reactions among 19 substances or groups of substances (permitting manipulation of 30 independent variables). The model is divided into two compartments, in conformity with previous models based on indirect evidence, and it is found that this compartmentation is indeed the same as that indicated directly with specifically (14)C-labelled acetate and glucose. The movement of materials between the large and small compartments has been studied; glutamine appears to flow from the small to the large compartment, gamma-aminobutyrate in the reverse direction.
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74
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Shank RP, Aprison MH. The metabolism in vivo of glycine and serine in eight areas of the rat central nervous system. J Neurochem 1970; 17:1461-75. [PMID: 5471908 DOI: 10.1111/j.1471-4159.1970.tb00513.x] [Citation(s) in RCA: 136] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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75
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Abstract
Results are reported of a comparative study in vivo of the metabolism of [2-(14)C]-glucose and [1-(14)C]acetate in brains of rats intoxicated with triethyltin sulphate. The incorporation of (14)C from glucose into glutamate, glutamine, gamma-aminobutyrate and aspartate was greatly decreased. The incorporation of (14)C from acetate into these amino acids was unaffected. The experimental data indicated that the main action of triethyltin was to decrease the rate at which pyruvate formed from glucose is oxidized. Glycolysis was not inhibited. Changes in glucose metabolism in the brain are shown not to be directly due to hypothermia. Some of the advantages of measuring the labelling of intermediates at very short time intervals after the injection of the labelled glucose are demonstrated.
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76
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Patel AJ, Balázs R, Richter D. Contribution of the GABA bypath to glucose oxidation, and the development of compartmentation in the brain. Nature 1970; 226:1160-1. [PMID: 5447041 DOI: 10.1038/2261160a0] [Citation(s) in RCA: 45] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Machiyama Y, Balázs R, Hammond BJ, Julian T, Richter D. The metabolism of gamma-aminobutyrate and glucose in potassium ion-stimulated brain tissue in vitro. Biochem J 1970; 116:469-81. [PMID: 5435691 PMCID: PMC1185385 DOI: 10.1042/bj1160469] [Citation(s) in RCA: 80] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
1. The metabolism of gamma-aminobutyrate (GABA) was investigated in cerebral-cortex slices incubated in glucose-saline medium with [1-(14)C]GABA and [U-(14)C]-glucose as labelled substrates. 2. A rapid release of GABA from the tissue, amounting to 25-30% of the total, was observed on addition of 66m-equiv. of K(+)/1 to the medium; the liberation of other amino acids was relatively small. The effect was apparently specific for K(+); GABA was not released on addition of equivalent amounts of Na(+) or on increasing the respiration rate with 10mm-ammonium chloride. The results show that GABA behaves like the transmitter compounds (acetylcholine, catecholamines) on K(+) stimulation, and therefore now satisfies certain of the criteria required for a transmitter in mammalian brain. 3. The release of GABA from the tissue on addition of K(+) was followed by a slow re-uptake. The rate of uptake of GABA in a medium containing 5.9m-equiv. of K(+)/1 was more than four times that in a medium containing 66m-equiv. of K(+)/1. 4. The concentration of GABA in brain tissue incubated for 1h in a medium containing 66m-equiv. of K(+)/1 was about 50% higher than that observed under normal conditions. 5. There was evidence that exogenous [(14)C]GABA mixed with the endogenous pool(s), since the proportion of the total GABA released on K(+) stimulation was the same, and the specific radioactivity of the liberated GABA was close to that remaining in the tissue, whether the GABA was labelled by [1-(14)C]GABA from the medium or generated in the tissue from [(14)C]glucose. 6. On the basis of these findings and the observations outlined in the preceding papers it was possible to calculate the kinetic constants of GABA metabolism by computer simulation of the results. K(+) stimulation led to a 2.5-fold increase in the flux through the tricarboxylic acid cycle, whereas the flux in the GABA bypath was little affected; as a result the flux through the GABA bypath, which under normal conditions was 8% of that through the tricarboxylic acid cycle, decreased to 3-5%. 7. The metabolism of glutamine was greatly affected by K(+)-stimulation. The ratio of the concentration of glutamine in the slices to that in the medium, which under normal conditions was the smallest among the amino acids investigated, increased from about 17 to 63 in 1h. This effect was attributable partly to an uptake of glutamine from the medium (1.8mumol/h per g) and partly to a net increase in the total amount of glutamine (2.6mumol/h per g). At 1h after the addition of K(+) the net gain of glutamine could be accounted for by the decrease of glutamate. 8. Metabolic compartmentation was evident when brain-cortex slices were incubated in glucose-saline medium and the labelled substrate was [(14)C]GABA, since the specific radioactivity of glutamine exceeded that of glutamate. On addition of K(+) the signs of metabolic compartmentation promptly disappeared: this effect was apparently associated with an increase in the permeability of the compartments containing labelled metabolites derived from [(14)C]GABA. The change in the permeability, however, did not affect all the compartments; when the labelled substrate was [(14)C]glucose the equilibration of labelled amino acids between tissue and medium was similar under normal conditions and in the presence of high concentrations of K(+). 9. The metabolism of [(14)C]glucose was followed by measuring oxygen uptake, respiratory (14)CO(2), and incorporation of (14)C into amino acids. The results showed that K(+) stimulation increased the flux of glucose carbon, both in the glycolytic pathway and in the tricarboxylic acid cycle.
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79
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Balázs R, Machiyama Y, Hammond BJ, Julian T, Richter D. The operation of the gamma-aminobutyrate bypath of the tricarboxylic acid cycle in brain tissue in vitro. Biochem J 1970; 116:445-61. [PMID: 5435689 PMCID: PMC1185383 DOI: 10.1042/bj1160445] [Citation(s) in RCA: 277] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
1. Cerebral-cortex slices prelabelled with gamma-amino[1-(14)C]butyrate (GABA) were incubated in a glucose-saline medium. After the initial rapid uptake there was no appreciable re-entry of (14)C into the GABA pool, either from the medium or from labelled metabolites formed in the tissue. The kinetic constants of GABA metabolism were determined by computer simulation of the experimental results by using mathematical procedures. The GABA flux was estimated to be 0.03mumol per min/g, or about 8% of the total flux through the tricarboxylic acid cycle. It was found that the assumption of compartmentation did not greatly affect the estimates of the GABA flux. 2. The time-course of incorporation of (14)C into amino acids associated with the tricarboxylic acid cycle was followed with [1-(14)C]GABA and [U-(14)C]-glucose as labelled substrates. The results were consistent with the utilization of GABA via succinate. This was confirmed by determining the position of (14)C in the carbon skeletons of aspartate and glutamate formed after the oxidation of [1-(14)C]GABA. These results also indicated that under the experimental conditions the reversal of reactions catalysed by alpha-oxoglutarate dehydrogenase and glutamate decarboxylase respectively was negligible. The conversion of [(14)C]GABA into gamma-hydroxybutyrate was probably also of minor importance, but decarboxylation of oxaloacetate did occur at a relatively slow rate. 3. When [1-(14)C]GABA was the labelled substrate there was evidence of a metabolic compartmentation of glutamate since, even before the peak of the incorporation of (14)C into glutamate had been reached, the glutamine/glutamate specific-radioactivity ratio was greater than unity. When [U-(14)C]glucose was oxidized this ratio was less than unity. The heterogeneity of the glutamate pool was indicated also by the relatively high specific radioactivity of GABA, which was comparable with that of aspartate during the whole incubation time (40min). The rates of equilibration of labelled amino acids between slice and medium gave evidence that the permeability properties of the glutamate compartments labelled as a result of oxidation of [1-(14)C]GABA were different from those labelled by the metabolism of [(14)C]glucose. The results showed therefore that in brain tissue incubated under the conditions used, the organization underlying metabolic compartmentation was preserved. The observed concentration ratios of amino acids between tissue and medium were also similar to those obtaining in vivo. These ratios decreased in the order: GABA>acidic acids>neutral amino acids>glutamine. 4. The approximate pool sizes of the amino acids in the different metabolic compartments were calculated. The glutamate content of the pool responsible for most of the labelling of glutamine during oxidation of [1-(14)C]GABA was estimated to be not more than 30% of the total tissue glutamate. The GABA content of the ;transmitter pool' was estimated to be 25-30% of the total GABA in the tissue. The structural correlates of metabolic compartmentation were considered.
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Van den Berg CJ, Krzalić L, Mela P, Waelsch H. Compartmentation of glutamate metabolism in brain. Evidence for the existence of two different tricarboxylic acid cycles in brain. Biochem J 1969; 113:281-90. [PMID: 5808317 PMCID: PMC1184634 DOI: 10.1042/bj1130281] [Citation(s) in RCA: 153] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
1. (14)C from [1-(14)C]glucose injected intraperitoneally into mice is incorporated into glutamate, aspartate and glutamine in the brain to a much greater extent than (14)C from [2-(14)C]glucose. This difference for [1-(14)C]glucose and [2-(14)C]glucose increases with time. The amount of (14)C in C-1 of glutamate increases steadily with time with both precursors. It is suggested that a large part of the glutamate and aspartate pools in brain are in close contact with intermediates of a fast-turning tricarboxylic acid cycle. 2. (14)C from [1-(14)C]acetate and [2-(14)C]acetate is incorporated to a much larger extent into glutamine than into glutamate. An examination of the time-course of (14)C incorporated into glutamine and glutamate reveals that glutamine is not formed from the glutamate pool, labelled extensively by glucose, but from a small glutamate pool. This small glutamate pool is not derived from an intermediate of a fast-turning tricarboxylic acid cycle. 3. It is proposed that two different tricarboxylic acid cycles exist in brain.
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81
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Threlfall CJ, Heath DF. Compartmentation between glycolysis and gluconeogenesis in rat liver. Biochem J 1968; 110:303-12. [PMID: 5726210 PMCID: PMC1187210 DOI: 10.1042/bj1100303] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
1. The specific radioactivity-time relationships of glucose, glucose 6-phosphate, glycerol 1-phosphate and UDP-glucose were determined in rat liver after the intravenous injection of [U-(14)C]fructose, and a kinetic analysis was carried out. The glucose 6-phosphate pool was found to be compartmented into gluconeogenic and glycolytic components, and evidence was obtained that the triose phosphates were similarly compartmented. The glycolytic pathway was fed by glycogenolysis and glucose phosphorylation. There was no direct evidence that glycogenolysis fed only the glycolytic pathway, but this interpretation would make the liver resemble other organs in this respect. 2. UDP-glucose was not formed solely from gluconeogenic glucose 6-phosphate, as there was some dilution of label in the intervening glucose 1-phosphate pool, probably from glycogenolysis, though other pathways cannot be excluded. 3. The data cannot be explained by isotopic exchange.
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84
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Baxter CF. Intrinsic amino acid levels and the blood-brain barrier. PROGRESS IN BRAIN RESEARCH 1968; 29:429-50. [PMID: 5735119 DOI: 10.1016/s0079-6123(08)64173-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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86
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Van Gelder NM. A possible enzyme barrier for gamma-aminobutyric acid in the central nervous system. PROGRESS IN BRAIN RESEARCH 1968; 29:259-71. [PMID: 5735305 DOI: 10.1016/s0079-6123(08)64161-8] [Citation(s) in RCA: 38] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Abstract
1. In a study of the metabolism of l-[(35)S]methionine in vivo, the labelled sulphur compounds of rat liver and brain were separated first by ion-exchange chromatography into two fractions containing (i) free sulphur amino acids such as methionine, cystathionine, cyst(e)ine and homocyst(e)ine and (ii) glutathione. 2. Two-dimensional paper chromatography with butan-1-ol-acetic acid or propionic acid-water in the first direction and 80% acetone or acetone-ethyl methyl ketone-water in the second direction was found superior to other solvent systems for separating the sulphur amino acids. 3. At 10min. after injection of [(35)S]methionine only a small part of the (35)S was found combined in free methionine or other free sulphur amino acids. 4. Evidence was obtained of the presence of adenosyl[(35)S]methionine and adenosyl[(35)S]homocysteine in perchloric acid extracts of rat liver and brain. 5. The trans-sulphuration pathway was active in brain as well as in liver.
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88
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Minard FN, Mushahwar IK. Synthesis of gamma-aminobutyric acid from a pool of glutamic acid in brain after decapitation. Life Sci 1966; 5:1409-13. [PMID: 5968706 DOI: 10.1016/0024-3205(66)90116-0] [Citation(s) in RCA: 76] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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90
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Van den Berg CJ, Mela P, Waelsch H. On the contribution of the tricarboxylic acid cycle to the synthesis of glutamate, glutamine and aspartate in brain. Biochem Biophys Res Commun 1966; 23:479-84. [PMID: 5961085 DOI: 10.1016/0006-291x(66)90753-4] [Citation(s) in RCA: 49] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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