Effect of Metrazol convulsions on 35S entry into cat central nervous system

Abstract

Cats injected with Na2S35O4 were convulsed with pentylenetetrazol (PTZ) for 5min. before sacrifice. Radioassay of 15 anatomical areas of brain revealed marked increases in the sulfate-S35 levels of the thalamus, geniculate bodies, and cerebral cortex. All changes were reversible by 1 hr. Convulsions did not produce expansion of the sulfate space nor increase in the per-cent of sulfate-S35 metabolized. Regional increases in sulfate exchange can be correlated with known sites of electrophysiologic dischrage. This technique may provide a useful method for identifying neuronal regions which are activated by convulsant agents. Regional increases were also noted with anesthesia and craniectomy suggesting that physiologic and metabolic factors secondary to neuronal activation per se may be involved in producing the increases observed.