Angiotensin II receptors negatively coupled to adenylate cyclase in rat aorta

Abstract

Angiotensin II (AII) inhibited adenylate cyclase from rat aorta in a concentration dependent manner. The maximal inhibition (approximately 20%) was observed at 10 microM. The inhibitory effect of angiotensin II was dependent on monovalent cations such as Na+ or Li+ and was blocked by saralasin, an antagonist of angiotensin. Guanine nucleotides such as GTP or GMP-P (NH)P were also required to elicit the inhibition by angiotensin II. In addition, angiotensin II also inhibited the stimulation exerted by catecholamines. These data suggest that angiotensin receptors are present in aorta which are negatively coupled to adenylate cyclase.