Continuous measurement of gastric nitric oxide production.
Neman, Anders, Johan Snygg, Lars Fndriks & Anders Pettersson.
Departments of Anesthesiology and Intensive Care, Clinical
Pharmacology and Center for Gastroenterological Research, Sahlgrens
University Hospital, S-413 45 Gsteborg, Sweden
APStracts 3:0117G, 1996.
Using a double-lumen catheter, nitric oxide (NO) was dialyzed across a
GORETEX_ membrane into a gas phase and subsequently analyzed on line
by chemiluminescence. This new technique for the continuous
measurement of NO was evaluated benchside and applied in the human
stomach in vivo to measure the nonenzymatic formation of NO generated
from nitrite in an acidic milieu. A linear relation (r2=0.991,
p<0.0001) between concentrations of NO in aqueous solutions
(2,5-52,5 mM) and NO in the corresponding gas phases obtained by the
dialysis-technique (50-1000 ppb), validated the present method for
quantitative analyses of NO. Inter- and intraassay coefficients of
variation at all concentrations of NO for 6 experiments were less
than 5%. High intragastric concentrations of NO (in the [mu]M range)
were found during basal conditions. The requirement of both nitrite
from the saliva and an acidic environment for NO formation is
indicated since depletion of saliva as well as acid neutralization
greatly reduced gastric NO concentrations. Furthermore, large amounts
of gastric NO were formed after intake of sodium nitrate. Using this
technique, NO can be continuously measured with accuracy
experimentally and clinically in any organ accessible to intubation.
Received 23 October 1995; accepted in final form 26 May 1996.
APS Manuscript Number G462-5.
Article publication pending Am. J. Physiol. (Gastrointest. Liver
Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 28 June 96