Effects of angiotensin, vasopressin, and methoxamine on cardiac function and blood flow distribution in conscious dogs

G. R. Heyndrickx, D. H. Boettcher, S. F. Vatner

Research output: Contribution to journalArticlepeer-review

181 Scopus citations


A comparison was made of the effects of vasopressin (ADH), methoxamine (MX), and angiotensin II (AN) on coronary and left ventricular dynamics, cardiac output, and regional blood flow distribution in intact, conscious dogs. At an equal percent pressure elevation, ADH reduced cardiac output and cardiac rate the most, while AN had the least effect. After denervation of arterial baroreceptors, ADH still reduced heart rate, while AN increased it, suggesting nonbaroreceptor negative and positive chronotropic effects, respectively. A differential pattern on peak dP/dt was also observed, with ADH causing a greater reduction than MX while AN did not decrease dP/dt. With heart rate held constant, AN did not reduce dP/dt, suggesting a direct positive inotropic effect since dP/dt should have fallen slightly due to reflex mechanisms, as was observed with MX and ADH. ADH induced the greatest increase in coronary resistance (140%), while the least (46%) was observed with AN, which could be explained, in part, by the differential effects observed on cardiac rate and contractility. The greatest increase in resistance in the iliac bed occurred with ADH (307%), and the least with AN (34%). Conversely, the greatest constriction in the renal bed occurred with AN (95%), and lesser amounts were observed with ADH (36%) and MX (35%). Thus ADH, MX, and AN exert potent yet differential vasoconstricting actions on peripheral beds. In addition, while all three agents elicited coronary vasoconstriction, the differential effects on coronary vascular resistance appeared to be due predominantly to a difference in chronotropic and inotropic actions.

Original languageEnglish (US)
Pages (from-to)1579-1587
Number of pages9
JournalAmerican Journal of Physiology
Issue number5 (I)
StatePublished - 1976
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Physiology (medical)

Fingerprint Dive into the research topics of 'Effects of angiotensin, vasopressin, and methoxamine on cardiac function and blood flow distribution in conscious dogs'. Together they form a unique fingerprint.

Cite this