Antalarmin blockade of corticotropin releasing hormone-induced hypertension in rats

Central administration of CRH results in endocrinological. cardiovascular, and behavioral effects that suggest stress or anxiety. Among these is a marked presser response. Parenteral administration of CRH, however, results in hypotension. We used parenteral administration of antalarmin, a novel, small molecule CRH1 receptor antagonist, and alpha -helical CRH9-41, a peptidic CRHR1/CRHR2 antagonist to attempt to determine the receptor mechanisms through which CRH is acting in both of these situations. Our results suggest that the hypertension produced by central CRH administration is mediated through central CRHR1 receptors, whereas the hypertension produced by parenteral CRH administration is mediated through peripheral CRHR2 receptors. (C) 2000 Elsevier Science B.V. All rights reserved.