AJP - Gastrointestinal and Liver Physiology, Vol 238, Issue 1 50-G56, Copyright © 1980 by American Physiological Society
Role of histamine H1- and H2-receptors in myoelectric activity of small bowel in the dog
S. J. Konturek and R. Siebers
Studies were conducted in conscious dogs implanted with monopolar silver
electrodes along the small intestine to determine whether the intestinal
motility response to histamine is mediated by H1-receptors alone or whether
H2-receptors are also involved in the response. Histamine infusion alone
induced a marked increase in the appearance rate and the propagation
velocity of the interdigestive myoelectric complexes (IMC). This effect was
reproduced by the administration of the selective H1-receptor agonist,
2-methylhistamine, and abolished by the H1-receptor antagonist,
tripelennamine. Tripelennamine alone decreased the frequency of occurrence
of the IMC in fasted animals and reduced significantly the spike potential
activity of the small bowel in fed dogs. Neither the H2-receptor agonist,
dimaprit, nor the H2-receptor antagonist, metiamide, had any influence on
the motility patterns in fasted or fed animals. We conclude that histamine
influences the patterns of small bowel motility via stimulation of
H1-receptors but its physiological role in modulating intestinal motility
remains to be determined.
