Cerebral energy state and glycolytic metabolism during lidocaine infusion in the rat.

The effects of intravenously administered lidocaine on the cerebral cortical energy state and glycolytic metabolism were studied in rats. In one series, rats were divided into five groups according to EEG patterns, i.e., control, desynchronized, synchronized, seizure (1-min duration) and recovery groups. With lidocaine infusion (0.75 mg/min), there were no significant changes from the control group in the cerebral energy state except for a modest increase in phosphocreatine (PCr) in the seizure group and a small decrease in ADP in the non-seizure groups. The cerebral energy charge remained unchanged. Lactate and pyruvate significantly decreased in the non-seizure groups. In a second series, rats were divided into five groups, i.e., control, lidocaine seizure groups (5-min duration, 1.5 mg/min) at hypocapnia, normocapnia and hypercapnia, and a bicuculline (1.2 mg/kg) seizure group. The metabolic changes during lidocaine seizure were essentially the same as those observed in the seizure group in the first series. However, the increase in PCr during lidocaine seizure was significant only in the hypocapnic and the normocapnic groups. Bicuculline-induced seizures were accompanied by a significant decrease in high energy phosphates. In summary, neither a non-seizure nor-seizure dose of lidocaine caused any reduction in the cerebral energy charge nor was there any evidence of increased anaerobic metabolism in the cerebral cortex during lidocaine-induced seizures.