Commentary

Abstract

The effects of lysergide, ephedrine, and nimergoline on the metabolizing ability (demethylation and acetylation of aminopyrine and glucuronoconjugation of oxazepam) of the dog brain isolated in situ were tested. The intracarotid perfusion with lysergide did not induce significant variations in aminopyrine and oxazepam metabolism, while the perfusion with ephedrine or nimergoline significantly increased the disappearance of the tested substances from the extracorporeal circuit, with an increase of some metabolic products. Activation of the tested biotransformation was accomplished by a decrease in cerebral vascular resistance and an increase in oxygen consumption. The action of lysergide, ephedrine, and nimergoline on the depression of the cerebral activity by hypoxia in dogs also was studied. Only ephedrine and nimergoline significantly improved the partial spontaneous reversion of the electroencephalogram depression, accomplished by a recovery of some enzymes (glutamic oxalacetic transaminase, lactate dehydrogenase, and alkaline phosphatase) in the cerebrospinal fluid, which was altered by the condition of hypoxia.