Hippocampal electrical activity and gamma-aminobutyrate metabolism in brain tissue following administration of homocysteine.

The concentration of gamma-aminobutyrate (GABA) and the activity of glutamate decarboxylase and GABA-transaminase were measured in extracts of mouse brain before the onset and during the course of generalized seizures induced by systemic administration of homocysteine thiolactone. The results indicate that whole brain GABA metabolism is unaffected by subconvulsive and convulsive doses of homocysteine at all stages of the generalized seizure. Electroencephalographic monitoring of rat brain electrical activity via hippocampal electrode implantation allowed the course homocysteine-induced seizures to be followed and afforded a means of quantifying such seizures.