Faculty Collaboration Database

Regional autoregulatory responses during infusion of vasoconstrictor agents in conscious dogs. Am J Physiol 1990 Oct;259(4 Pt 2):H1270-7

Date

10/11/1990

Pubmed ID

2221130

DOI

10.1152/ajpheart.1990.259.4.H1270

Scopus ID

2-s2.0-0025016252 (requires institutional sign-in at Scopus site)   29 Citations

Abstract

We investigated pressure-dependent autoregulatory responses in mesenteric, iliac, and renal vascular beds of conscious dogs during intravenous infusion of angiotensin II, phenylephrine, or arginine vasopressin at rates which increased arterial pressure by 20-40 mmHg. The arteries supplying these beds were instrumented with an electromagnetic flow probe, a nonoccluding catheter, and an electromagnetic flow probe, a nonoccluding catheter, and an occluder cuff connected with a servo-amplifier, which enabled us to return perfusion pressure to control levels during infusion of the vasoconstrictor agents. We attempted to differentiate between the increase in vascular resistance due to the direct effect of the vasoconstrictor agent and the increase induced by an autoregulatory response induced by elevations of aortic perfusion pressure. We measured a strong degree of autoregulation in the renal vascular bed with a fractional compensation value close to 1. Moderate autoregulation occurred in the mesenteric vascular bed, where the compensation was 0.4-0.5 with angiotensin II and phenylephrine and between 0.74 and 0.94 with vasopressin. No autoregulatory capacity could be demonstrated in the hindlimb. The findings indicate that, under conditions of increased systemic blood pressure, both the renal and the mesenteric vascular beds contribute to the increase in total peripheral resistance by pressure-dependent vasoconstrictor responses.

Author List

Hellebrekers LJ, Liard JF, Laborde AL, Greene AS, Cowley AW Jr

Author

Allen W. Cowley Jr PhD Professor in the Physiology department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Angiotensin II
Animals
Arginine Vasopressin
Blood Pressure
Consciousness
Dogs
Female
Hindlimb
Homeostasis
Ilium
Infusions, Intravenous
Male
Phenylephrine
Rats
Renal Circulation
Splanchnic Circulation
Vascular Resistance
Vasoconstrictor Agents