Angiotensin II mediated ACTH release in rat pituitary cell culture

Anterior pituitaries from normal rats were enzymatically dispersed and placed into monolayer cell culture in order to determine if and how angiotensin II (Ang II) mediates the in vitro release of ACTH and other pituitary hormones. Ang II stimulated ACTH secretion in a time dependent fashion. This release occurred at physiologic concentrations of Ang II and was linearly correlated with the log dose of Ang II. One hour pretreatment of the cells with cycloheximide, a inhibitor of protein synthesis, significantly decreased the cellular ACTH secretory response to Ang II. Ang 11 did not mediate the release of LH nor of ADH, a proposed stimulator of ACTH secretion.