Changes in cerebral glycogenolysis and related enzymes in diazinon treated hyperglycaemic animals

Effect of diazinon (10,20 and 40 mg/kg, i.p.) on the level of blood glucose in rats was investigated. Hyperglycaemia peaked 2 h after i.p. treatment with 40 mg/kg diazinon. The cerebral acetylcholinesterase activity was significantly reduced. The blood level of pyruvic acid was unchanged while that of lactic acid was significantly increased. Convulsions and biochemical changes caused by diazinon (40 mg/kg) were prevented by diazepam injected immediately after diazinon. In diazinon-treated hyperglycaemic animals, the glycogen content of the brain was depleted, the activities of glycogen phosphorylase, phosphoglucomutase and hexokinase were significantly increased and the activity of glucose-6-phosphatase remained unchanged. Lactate dehydrogenase activity was also increased by treatment with diazinon. The induced changes may compensate for the energy requirement of stimulatory effects caused by diazinon.