(Des-Asp1) angiotensin I: a study of its pressor and steroidogenic activities in conscious rats. Endocrinology 1977 Jan;100(1):46-51
Date
01/01/1977Pubmed ID
187407DOI
10.1210/endo-100-1-46Scopus ID
2-s2.0-0017367254 (requires institutional sign-in at Scopus site) 28 CitationsAbstract
The steroidogenic and pressor activities of the nonapeptide (des-Asp1) angiotensin I [(des-Asp)-AI] were tested in conscious rats. (des-Asp)-AI caused dose related increases in mean arterial pressure (MAP), serum aldosterone, and serum corticosterone in doses between 3 and 3,000 ng/kg/min. (des-Asp)-AI was 14% as potent as angiotensin I and angiotensin II and 60% as potent as (des-Asp1) angiotensin II [des-Asp)-AII] in raising MAP. (des-Asp)-AI was less active than AI, AII, or (des-Asp)-AII in causing increased release of aldosterone, possessing only 8%, 11%, and 17% of the potency of AII, (des-Asp)-AII, and AI, respectively. Each of these angiotensin peptides was equally potent in elevating serum corticosterone levels. Infusions of a nonapeptide inhibitor of converting enzyme (CEI, 0.5 mg/kg/min iv) did not alter control MAP or blood pressure responses to AII or (des-Asp-)-AII but inhibited equally the blood pressure effects of AI and (des-Asp)-AI. CEI also inhibited the ability of (des-Asp)-AI (67% inhibition) and AI (34% inhibition) to increase the serum aldosterone concentration, but had no effect on basal aldosterone levels. These data indicate that (des-Asp)-AI has pressor and steroidogenic effects, but requires conversion to (des-Asp)-AII for a major portion of its activity. These results further substantiate the hypothesis that (des-Asp)-AII, recently recognized as a hormone of the renin-angiotensin system, may be produced without the formation of AII as an intermediate and provide in vivo evidence for the conversion of (des-Asp)-AI to (des-Asp)-AII.
Author List
Campbell WB, Schmitz JM, Itskovitz HDAuthor
William B. Campbell PhD Professor in the Pharmacology and Toxicology department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AldosteroneAngiotensin II
Angiotensin III
Angiotensin-Converting Enzyme Inhibitors
Animals
Blood Pressure
Corticosterone
Dose-Response Relationship, Drug
Male
Rats
Structure-Activity Relationship