AJP - Gastrointestinal and Liver Physiology, Vol 259, Issue 1 21-G25, Copyright © 1990 by American Physiological Society
Bile acids do not mediate the hyperdynamic circulation in portal hypertensive rats
P. Genecin, J. Polio, L. A. Colombato, G. Ferraioli, A. Reuben and R. J. Groszmann
Hepatic Hemodynamic Laboratory, Veterans Administration Medical Center, West Haven, Connecticut 06516.
Portal hypertension is accompanied by hyperdynamic systemic and splanchnic
circulation. Serum bile acids (BAs), which are elevated in portal
hypertension and have vasodilatory properties, have been proposed as
mediators of this hyperdynamic circulation. In this study, portal
hypertensive rats [accomplished by partial portal vein ligation (PVL)] were
gavaged with cholestyramine (PVL-CH) to decrease circulating BA levels. A
control group of rats was gavaged with an inert suspension of Metamucil
(PVL-ME). The following hyperdynamic parameters were found to be similar in
PVL-CH and PVL-ME: mean arterial pressure (119 +/- 6 vs. 124 +/- 5 mmHg),
portal pressure (13.2 +/- 0.6 vs. 14.5 +/- 0.5 mmHg), cardiac index (0.33
+/- 0.04 vs. 0.34 +/- 0.03 ml.min-1.g body wt-1), splanchnic blood flow
(1.4 +/- 0.13 vs. 1.6 +/- 0.1 ml.min-1.g body wt-1), portosystemic shunting
(82 +/- 8 vs. 92 +/- 3%), peripheral arteriolar resistances (344 +/- 74 vs.
387 +/- 29 mmHg.min.ml-1.g body wt), and splanchnic arteriolar resistances
(75 +/- 14 vs. 72 +/- 6 mmHg.min.ml-1.g splanchnic wt; 1,471 +/- 150 vs.
1,325 +/- 120 mmHg.min.ml-1.g body wt). BA in PVL-ME (84 +/- 9 microM/l)
were similar to those previously observed in untreated PVL and
significantly greater than those measured in PVL-CH (25 +/- 4 microM/l; P
less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)
