Inhibition of the rate of GABA synthesis in regions of rat brain following a convulsion.
1 The rate of synthesis of gamma-aminobutyric acid (GABA) in the cortex, hippocampus and striatum of rat brain was assessed by measuring the linear rate of accumulation of GABA following injection of amino-oxyacetic acid (AOAA). 2 Five min after a single electrically induced seizure there was a rise in GABA content in these brain regions and an almost total inhibition of the rate of synthesis. 3 Five min after seizure induced by the inhalant convulsant flurothyl there was no rise in GABA content in these brain regions but a similar marked degree of inhibition of GABA synthesis. 4 Two hours after the convulsion the rate of GABA synthesis had returned to control values in all three brain regions. 5 A single convulsion did not alter the glutamic acid decarboxylase activity in these brain regions either in the absence or presence of added co-factor (pyridoxal phosphate). 6 Evidence for an inhibition of GABA release following a convulsion which may be associated with the inhibition of GABA synthesis is presented in the following paper.
Green
A R
AR
MRC Clinical Pharmacology Unit, Radcliffe Infirmary, Oxford.
Metz
A
A
Minchin
M C
MC
Vincent
N D
ND
D000625:Aminooxyacetic Acid / Q000494:pharmacology; D000818:Animals; D001921:Brain / Q000201:enzymology / Q000378:metabolism*; D005481:Flurothyl / Q000633:toxicity; D008401:Gas Chromatography-Mass Spectrometry; D005968:Glutamate Decarboxylase / Q000378:metabolism; D007700:Kinetics; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012640:Seizures / Q000139:chemically induced / Q000378:metabolism*; D013997:Time Factors; D005680:gamma-Aminobutyric Acid / Q000096:biosynthesis*
D000625:Aminooxyacetic Acid; D005680:gamma-Aminobutyric Acid; D005481:Flurothyl; D005968:Glutamate Decarboxylase