Differential Action of Chlorpromazine on Reflexes Conditioned to Central and Peripheral Stimulation

Abstract

Cats chronically prepared with implanted electrodes are trained to respond with a foot flexion equally well to electrical stimulation of the cerebral cortex and to tonal or photic (peripheral) stimuli. Under appropriate doses of chlorpromazine a greater depression of peripherally induced flexions as compared with those cortically elicited is observed in most animals. At an average of 7 mg/kg the depression is complete to peripheral stimuli whereas cortical stimulation can elicit a moderate number of flexions. This differential action is not obtained with LSD-25, morphine sulfate, or pentobarbital sodium. Reserpine results are inconclusive but indicate some similarity to chlorpromazine. Drug effects on afferent systems are discussed.