AJP - Heart and Circulatory Physiology, Vol 251, Issue 5 991-H999, Copyright © 1986 by American Physiological Society
Lack of liver vascular response to carotid occlusion in mildly acidotic dogs
C. A. Goresky, D. Cousineau, C. P. Rose and S. Lee
The effect of mild acidosis on the reduction in liver vascular volume
provoked by reflex sympathetic activation was ascertained in dogs by use of
the multiple indicator-dilution technique. Portal vein-hepatic vein
dilution patterns were obtained following injection of a mixture containing
51Cr-labeled red blood cells (a vascular reference), 14C-labeled sucrose
(an interstitial reference), and 3H-labeled water (a cellular reference).
Liver vascular, interstitial, and cellular water spaces were measured in
normal and mildly acidotic dogs under basal conditions and during bilateral
carotid artery occlusion. Carotid occlusion resulted in a large increase in
arterial blood pressure in normal and a lesser increase in acidotic dogs,
but the increase in portal and hepatic vein norepinephrine and decrease in
liver vascular and interstitial volumes observed in normal dogs did not
occur in the acidotic animals; no change in labeled water accessible liver
cellular spaces was perceptible. The data indicate that mild acidosis
abolishes the ordinarily expected reduction in liver vascular volumes on
sympathetic activation in the intact dog but not the arterial pressor
response.
