PT - JOURNAL ARTICLE AU - W B Campbell AU - W A Pettinger TI - Organ specificity of angiotensin II and Des-aspartyl angiotensin II in the conscious rat. DP - 1976 Aug 01 TA - Journal of Pharmacology and Experimental Therapeutics PG - 450--456 VI - 198 IP - 2 4099 - http://jpet.aspetjournals.org/content/198/2/450.short 4100 - http://jpet.aspetjournals.org/content/198/2/450.full SO - J Pharmacol Exp Ther1976 Aug 01; 198 AB - Des-Asp angiotensin II (des-Asp AII) is a naturally occurring heptapeptide metabolite of angiotensin II (AII) which is formed by the enzymatic action of aminopeptidase A. Angiotensin II and des-Asp AII were infused into unanesthetized rats while direct mean arterial pressure, serum aldosterone and serum corticosterone were measured. Both AII and des-Asp AII caused a dose-related increase in serum aldosterone with a significant increase occurring with a dose as low as 1 ng/min. This effect was blocked by pretreatment with 1-Sar-8-Ala-angiotensin II, a competitive inhibitor of AII; however, the inhibitor was more effective in blocking the effects of AII (101%) than of des-Asp AII (82%). Both angiotensins induced a dose-related increase in serum corticosterone and mean arterial pressure. Des-Asp AII was however only 1/10 as potent as AII in elevating mean arterial pressure. 1-Sar-8-Ala-AII was also effective in inhibiting the pressor effects of AII and des-Asp AII. These data illustrate a high degree of organ specificity or selectivity for des-Asp AII and a low specificity for AII. Aminopeptidase A and leucine aminopeptidase were identified in the adrenal cortex and medulla in large amounts. Des-Asp AII may thus be formed from AII locally in the adrenal gland prior to exerting its action at that site.