EFFECTS OF KAINATE-INDUCED SEIZURES ON CEREBRAL METABOLISM - A COMBINED H-1 AND P-31 NMR-STUDY IN RAT

The cerebral metabolic changes elicited by kainate-induced seizures in the rat were investigated by in vivo combined NMR spectroscopy of P-3 1 and H-1. Systemic injection of kainate induced no significant change s in cerebral ATP or PCr levels during up to 90 min of continuous, gen eralised seizures, and the cerebral P-31 spectra showed only a transie nt mild cerebral acidosis 30 min after kainate administration. In para llel with the changes in intracellular cerebral pH, the H-1 spectra sh owed a significant increase in lactate, which remained elevated throug hout the seizures. These findings indicate that oxidative metabolism d oes not completely match the increased glycolysis during seizures thou gh the energy homeostasis is maintained. This suggests that oxidative metabolism has a limited capacity to satisfy the brain's energy needs during the kainate-induced seizures, but that the different pathways o f energy production in the brain cells can overcome this limitation. T hus the brain damage associated with this experimental model of epilep sy is not due to extended major failure of the energy supply.