PLASMA 17-HYDROXYCORTICOSTEROID RESPONSE TO HYPOTHALAMIC STIMULATION IN THE CONSCIOUS RHESUS MONKEY

Abstract

A technique for the study of plasma hormone concentrations during electrical stimulation of selected deep brain areas in conscious monkeys through chronically implanted electrodes is described. The experimental conditions permit repeated study of an individual animal during periods of rest and during a variety of control and experimental procedures, so that an animal can be considered to furnish his own control data. Stimulation of the hypothalamus is associated with an increase in pituitary-adrenal cortical activity, as judged by a marked elevation of plasma 17-OH-CS levels (20-25 /ig.%/hr.) A closely similar rate of rise in plasma 17-OH-CS levels (20-25 ng. %/ hr.) was observed in the same animals after intravenous injection of ACTH (16 mg./kg.). No significant changes in plasma 17-OH-CS levels were observed under normal conditions or during control stimulation of the putamen or anterior thalamus.