AJP - Gastrointestinal and Liver Physiology, Vol 248, Issue 3 369-G375, Copyright © 1985 by American Physiological Society
Effect of pentagastrin on gastric mucosal histamine in dogs
J. S. Redfern, R. Thirlby, M. Feldman and C. T. Richardson
We studied the effect of pentagastrin on histamine content of gastric
mucosa obtained from dogs with gastric fistulas to determine whether
pentagastrin mobilizes cellular stores of histamine. Experiments were also
performed on canine gastric mucosa in vitro to investigate the effects of
pentagastrin on histamine release, per se. During in vivo studies basal
histamine content averaged 0.9 nmol/mg wet wt tissue or 18.8 nmol/mg tissue
prot. No significant difference in gastric mucosal histamine content
occurred during intravenous administration of pentagastrin (6 or 16
micrograms . kg-1 . h-1) or saline (control), even though acid output from
the gastric fistula increased significantly above control during
pentagastrin infusion. Moreover, pentagastrin (10(-5) and 10(-8)M) did not
release more histamine from gastric mucosa in vitro than the buffer
(control), whereas Triton X-100 and the phorbol ester 4 beta-phorbol 12
beta-myristate 13 alpha-acetate, alone and in combination with calcium
ionophore A23187, released significant amounts of histamine above control
values. From these experiments we conclude that pentagastrin did not alter
histamine content of canine gastric mucosa in vivo, even though acid
secretion was stimulated maximally, nor did pentagastrin release histamine
in vitro.
