INFLUENCE OF CORTICOSTEROIDS AND CHLORPROMAZINE ON THE RELEASE OF VASOPRESSIN FROM ISOLATED NEURAL LOBES OF RATS

Abstract

ABSTRACT Isolated neural hemilobes from rats were stimulated with high concentrations of potassium during incubation with media containing corticotrophin, prednisolone, aldosterone or chlorpromazine. Corticotrophin or aldosterone did not influence the amount of vasopressin released during stimulation, whereas prednisolone in a concentration of 10 μg/100 ml medium caused a significant inhibition. It was found that low concentrations of chlorpromazine inhibited the stimulated release of vasopressin from isolated neural hemilobes, whereas high concentrations increased the release. The possible physiological significance of the results is discussed with particular reference to possible modulating effects of glucocorticoids on the release process of neurohypophyseal hormones.