AJP - Gastrointestinal and Liver Physiology, Vol 248, Issue 1 68-G72, Copyright © 1985 by American Physiological Society
Lipase secretion from dispersed rabbit gastric glands
C. S. Fink, M. Hamosh, P. Hamosh, S. J. DeNigris and D. K. Kasbekar
We have measured gastric lipase activity in dispersed glands of rabbit
stomach by quantitating the hydrolysis of tri[3H]olein. Lipase activity in
isolated gastric glands was 200-400 nmol [3H]oleic acid released per
milligram dry weight per minute. The percentage of lipase activity released
during incubation for 30 min at 37 degrees C under basal conditions was
1.5-4.5%. Lipase release was stimulated by secretagogues: 10 nM
cholecystokinin octapeptide (CCK-8) and 100 microM carbachol led to four-
to sixfold and two- to threefold higher enzyme secretion, respectively,
while histamine had no effect. Carbonyl cyanide m-chlorophenylhydrazone (30
microM) completely inhibited the CCK-8-induced lipase release, indicating
that lipase secretion is dependent on mitochondrial oxidative energy;
dibutyryl cGMP (1 mM) inhibited 1 nM CCK-8-stimulated but not 100 microM
carbachol-stimulated secretion; atropine (1 microM) had the opposite
effect. These studies suggest that secretion of lipase from isolated
gastric glands is stimulated by at least two receptor mechanisms. These
studies show that a lipase that hydrolyzes long-chain triglyceride is
secreted by rabbit stomach mucosa and that the secretion of gastric lipase
is stimulated by two different receptor mechanisms.
