AJP - Regulatory, Integrative and Comparative Physiology, Vol 262, Issue 2 289-R294, Copyright © 1992 by American Physiological Society
Area postrema stimulation induces differential renal hemodynamics with two anesthetics
D. K. Hartle and A. S. Soliman
Dept. of Pharmacology and Toxicology, College of Pharmacy, University of Georgia, Athens 30602.
The effect of area postrema stimulation (APS) on blood pressure, renal
blood flow (RBF), and renal vascular resistance was compared in
urethan-anesthetized and pentobarbital sodium-anesthetized Sprague-Dawley
rats. Mean arterial pressure (MAP) increased in a frequency-dependent
manner during APS in both urethan- and pentobarbital-anesthetized rats.
Although no significant differences occurred in the maximum percent change
in MAP between groups, marked differences occurred in RBF and calculated
renal vascular resistance (RVR) changes. In urethan-anesthetized rats, RBF
and MAP increased during APS, but RVR did not change. In contrast, APS
significantly decreased RBF (-26.5 +/- 1.9%) while increasing RVR (+99.4
+/- 11.4%) in pentobarbital-anesthetized rats. The increase in RVR in the
pentobarbital-anesthetized group during APS was eliminated by prior
ganglionic blockade. It was concluded that the anesthetic agent employed
can significantly alter the degree to which APS can activate renal
vasomotion in the rat.
