Jpn. J. Pharmacol. 85 (1), 109-113 (2001)

Is Compensatory Vasoconstrictor Tone in the Hindquarter Vascular Region Induced by Hemorrhage in Conscious Spontaneously Hypertensive Rats?

Yasuhiro Teranishi1,*, Noriko Iida1, Norio Ishioka2, Hiroshi Sugino2 and Taku Amano3

1Department of Physiology, 2First Department of Internal Medicine and 3Department of Pharmacology, Hiroshima University, Faculty of Medicine, Minami-ku, Hiroshima 734-8551, Japan
*Corresponding author. FAX: +81-82-257-5187

Abstract: We investigated whether a compensatory vasoconstrictor action would be induced by a hypotensive intervention in the hindquarter vascular region of conscious spontaneously hypertensive rats (SHRs). Mean arterial pressure and hindquarter blood flow were recorded. After hemorrhage (withdrawing blood, 0.3 ml/100 g body weight), hindquarter resistance (HQR) was increased significantly. The decrease in HQR induced by the administration of a ganglionic blocker (C6; 25 mg/kg, i.v.) was significantly greater in SHRs with hemorrhage than in those without hemorrhage. The present results suggest that a detectable hindquarter compensator tone occurs due to hemorrhage in SHRs, although an abnormal substantial vasoconstrictor tone already exists in the hindquarters.

Keywords: Hemorrhage, Hindquarter compensator, Spontaneously hypertensive rat

Copyright The Japanese Pharmacological Society

[Back to TOC]