Effect in vivo of some anticonvulsant drugs on mouse brain glutamate dehydrogenase. Animals received pyridoxal phosphate (PPAL, 50 mg/Kg), hydroxylamine (OHAMINE, 40 mg/kg), and aminooxyacetic acid (AAOA, 40 mg/Kg). After different times of treatment, glutamate dehydrogenase activity (GDH) was determined in brain homogenates (1 : 5 w : v on phosphates 0.05 M pH = 7.6 buffer) for oxidative deamination of glutamate and reductive amination of α-ketoglutarate, using a spectrophotometric method (see Section 2). Results are means ± SEM (). ANOVA test was applied and different characters were used to indicate statistically different groups as compared with the control (, Tuckey’s test).