This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Knight, D. R. Articles by Vatner, S. F. Search for Related Content PubMed PubMed Citation Articles by Knight, D. R. Articles by Vatner, S. F.

Hypertension, Vol 7, 380-385, Copyright © 1985 by American Heart Association

ARTICLES

Effects of a calcium channel blocker on cardiac output distribution in conscious hypertensive dogs

DR Knight, DA Kirby and SF Vatner

The effects of nitrendipine, 8 micrograms/kg/minute, were evaluated in six conscious dogs through measurements of arterial pressure and blood flow in the ascending aorta (cardiac output), mesenteric, renal, and iliac arteries before and after induction of chronic perinephritic hypertension. Before hypertension was induced, nitrendipine reduced mean arterial pressure 19 +/- 2.3% (from 95 +/- 3.2 mm Hg), decreased total peripheral resistance (60 +/- 2.6%), and increased cardiac output (108 +/- 10.5%). These values returned to baseline within 15 to 30 minutes. Nitrendipine caused the greatest increase in blood flow in the iliac bed (98 +/- 9.9%), an intermediate increase in the mesenteric bed (37 +/- 3.7%), and the least increase in the renal bed (7 +/- 2.2%). Two to six weeks after induction of hypertension, administration of nitrendipine elicited significant (p less than 0.01) decreases in mean arterial pressure (32 +/- 2.5% from 151 +/- 4.8 mm Hg) and total peripheral resistance (67 +/- 1.3%) compared with its administration in normotensive dogs, while the increase in cardiac output was not significantly changed (111 +/- 10.9%). These changes in arterial pressure and vascular resistances also were prolonged (i.e., hemodynamics returned to baseline after 75-90 minutes). The increase in iliac (99 +/- 16.8%) and renal (9 +/- 6.1%) blood flows after nitrendipine administration in hypertensive dogs was similar to that found in the normotensive dogs, but mesenteric blood flow doubled (84 +/- 8.4%). Thus, in conscious, hypertensive dogs, nitrendipine administration appears to markedly decrease arterial pressure and total peripheral and regional resistances, which also require more time to return to baseline, but appears to increase blood flow by a greater amount only in the mesenteric bed.

This article has been cited by other articles:

				F. Ohta, T. Takagi, H. Sato, and L. J. Ignarro Low-dose L-arginine administration increases microperfusion of hindlimb muscle without affecting blood pressure in rats PNAS, January 23, 2007; 104(4): 1407 - 1411. [Abstract] [Full Text] [PDF]