ENDOGENOUS AND EXOGENOUS VASOPRESSIN ON ACTH RELEASE1

Abstract

Simultaneous studies of the release of antidiuretic hormone (vasopressin, ADH) and corticotrophin (ACTH) were performed in unanesthetized trained dogs. Antidiuresis was used as the index of ADH liberation and plasma free 17-hydroxy-corticosteroid levels were used to indicate ACTH release. No correlation was observed between discharge of ACTH and release or inhibition of the release of ADH. Further studies with highly purified vasopressin showed that exogenous ADH was unable to stimulate the secretion of ACTH until a threshold of 3-7x 103 times the dose reproducing maximal physiologic antidiuresis was exceeded. The physiological significance of the data evidencing ACTH release upon injection of vasopression is debated and questioned.