Augmentation of ACTH-releasing activity of synthetic corticotropin releasing factor (CRF) by vasopressin in women.

In order to study the interaction between vasopressin (VP) and hypothalamic corticotropin releasing factor (CRF) on the release of ACTH, VP and CRF were administered separately and in combination to normal cycling women. The combined hormones raised plasma ACTH levels higher than the sum of the separate responses and 5 times more than CRF alone. This study reveals for the first time synergism between VP and CRF in their ACTH releasing effects in humans.