Inhibition of γ-Aminobutyric Acid Aminotransferase From Rat Brain Mitochondria by Chloride and Acetate

Abstract

10-100 mmol/1 of acetate inhibits γ-aminobutyric acid aminotransferase from rat brain mitochondria by 35-90% Similarly, 50-100 mmol/1 of chloride inhibits this enzyme by 10-30%. In either case, the inhibition is competitive with GABA and noncompetitive with α-ketoglutarate. The effect of sodium and potassium is negligible. γ-Aminobutyric acid aminotransferase from rat liver mitochondria is also inhibited by acetate and chloride. The degree of inhibition of both hepatic and cerebral enzyme is nearly the same.

Key Words: :

• γ-aminobutyric acid aminotransferase
• inhibition
• chloride
• acetate