Angiotensin stimulates beta-endorphin release from anterior pituitary gland cell cultures of rats

The effect of exogenous and locally generated angiotensin II (ANG II) on the release of beta-endorphin (beta-END) from anterior pituitary cell cultures of rats was studied. Angiotensin I (ANG I) and ANG II stimulated the release of beta-END, the ANG I effects being inhibited by addition of the converting enzyme inhibitor captopril. Renin and angiotensinogen had no effect when given separately, but their combination increased beta-END release. Thus ANG II causes the release of beta-END, but the putative pituitary renin system cannot be stimulated by exogenous renin or angiotensinogen; converting enzyme, however, acts locally to produce biologically active ANG II from ANG I.