Metabolism of the Perfused Cat Brain during Metrazol Convulsions and Electroshock

Abstract

THERE are a number of reports in the literature that during metrazol convulsions the rate of cerebral oxygen consumption increases^1–3. It is also generally accepted that normally cerebral oxidations proceed almost exclusively at the expense of glucose. In a previous report⁴, however, it was demonstrated with the aid of radioactive glucose that, in the case of cat brain perfused with ‘simplified blood’ (bovine red blood corpuscles suspended in Ringer's solution containing albumin), only about 30 per cent of the carbon dioxide produced by the brain comes from the blood glucose, while the rest of the carbon dioxide is derived from the combustion of endogenous substrates. This communication reports experiments showing an increase in production of carbon dioxide by the perfused cat brain following convulsions induced by metrazol and following electroshock. The results indicate that the major part of the excess carbon dioxide is derived from unknown endogenous substrates.