Effects of nitric oxide synthesis inhibition on mesenteric
perfusion in young pigs.
Alemany, Carlos A., William Oh, Barbara S. Stonestreet.
BROWN UNIVERSITY SCHOOL OF MEDICINE, DEPARTMENT OF PEDIATRICS,
WOMEN & INFANTS' HOSPITAL OF RHODE ISLAND, PROVIDENCE, RHODE
ISLAND 02905
APStracts 3:0216G, 1996.
We tested the hypothesis that nitric oxide modulates the postprandial
hyperemia in young pigs. To test this hypothesis, we studied five
groups of three week old pigs which were: Group 1: milk-fed, NG
-monomethyl-L-Arginine (L-NMMA), L-Arginine (L-Arg) treated (n=10);
Group 2: milk-fed, placebo treated (n=8); Group 3: water-fed, L-NMMA,
L-Arg treated (n=6); Group 4: water-fed, placebo treated (n=4); and
Group 5: fasted sham-fed L-NMMA, L-Arg treated (n=6). After catheter
placement and electromagnetic flow probe instrumentation of the
mesenteric artery, systemic blood pressure and mesenteric artery
blood flow were measured during preprandial-baseline, postprandial
and postprandial-intra-arterial L-NMMA and L-Arg infused study
periods. The same measures were made in the milk- and water-fed
placebo treated groups except that diluent replaced the L-NMMA and L
-Arg infusions. In the milk- and water-fed placebo treated groups, a
significant (ANOVA, p<0.05) postprandial hyperemia was
observed. The change in blood flow was greater (p<0.05) in the
milk- than the water-fed group. Inhibition of nitric oxide synthesis
with L-NMMA diminished (p<0.05) the hyperemic responses to
both water and milk feeding and resulted in a decrease
(p<0.05) in mesenteric artery perfusion in the fasted sham-fed
state. We conclude that, in young pigs, nitric oxide is a modulator
of mesenteric vascular tone in both the postprandial and fasted
states.
Received 23 April 1996; accepted in final form 30 September 1996.
APS Manuscript Number G147-6.
Article publication pending Am. J. Physiol. (Gastrointest. Liver
Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 5 November 1996