[Multineuronal activity of the paraventricular nucleus of the hypothalamus during activation and inhibition of the adrenocortical system]

Abstract

Multiunit activity of paraventricular nucleus and fornix was studied during activation and inhibition of the pituitary--adrenocortical system in chronic experiments on rabbits. Immobilization causing blood corticosteroid levels to rise was followed by the excitation of the neurons in paraventricular nucleus and by inhibition in the fornix. Administration of cortisol (100 micrograms/kg before the immobilization) causing inhibition of pituitary--adrenocortical system was followed by the inhibition of neurons in paraventricular nucleus and fornix. The activation of the paraventricular nucleus seems to be responsible for the activation of the pituitary--adrenocortical system whereas its inhibition induced the inhibition of this system.