Involvement of different mechanisms in the stimulatory effects of cholecystokinin octapeptide on gastrointestinal and colonic motility in dogs
- 1 October 1989
- journal article
- research article
- Published by Canadian Science Publishing in Canadian Journal of Physiology and Pharmacology
- Vol. 67 (10), 1205-1212
- https://doi.org/10.1139/y89-191
Abstract
The effects of an intravenous infusion of cholecystokinin octapeptide (CCK-8, 1 μg∙kg−1∙h−1) were investigated in conscious fasted dogs chronically fitted with strain-gauge transducers on the antrum, the jejunum, and the colon. Attempts to antagonize the increase of motility appearing at the three levels during CCK infusion were made using different blockers to elucidate the mechanisms involved. Asperlicin (a specific CCK antagonist) blocked the effects of CCK-8 at the three levels, while atropine and somatostatin were only effective in the jejunum and colon. Methyl-levallorphan (a μ-opiate antagonist that poorly crosses the blood-brain barrier) antagonized the CCK-induced colonic stimulation when intracerebroventricularly administered. Serotonin, histamine, substance P, and κ-antagonists as well as a benzodiazepine did not modify the CCK-8 induced stimulation. It was concluded that the stimulatory effect of CCK-8 resulted from (a) a direct stimulation of the smooth muscle cells at gastric level, (b) a cholinergic activation of the jejunum and the colon, and (c) the involvement of a μ-opioid central component in the colonic response only.Key words: cholecystokinin octapeptide, gastrointestinal motility, dog, cholecystokinin antagonists, opiates, cholinergic system.This publication has 26 references indexed in Scilit:
- The role of opiate receptors and cholinergic neurons in the gastrocolonic responseGastroenterology, 1982
- Receptors on smooth muscle cells: characterization by contraction and specific antagonistsAmerican Journal of Physiology-Gastrointestinal and Liver Physiology, 1982
- Proglumide and benzotript: members of a different class of cholecystokinin receptor antagonists.Proceedings of the National Academy of Sciences, 1981
- Antinociceptive effect of centrally administered caerulein and cholecystokinin octapeptide (CCK-8)European Journal of Pharmacology, 1981
- Cholecystokinin receptors: Presence and axonal flow in the rat vagus nerveLife Sciences, 1981
- The gastrocolic response: Evidence for a neural mechanismGastroenterology, 1979
- Electrical and mechanical effects of molecular variants of CCK on antral smooth muscle.American Journal of Physiology-Endocrinology and Metabolism, 1978
- Diurnal changes in gastric motor activity in conscious dogsDigestive Diseases and Sciences, 1977
- Effect of cholecystokinin on myoelectric activity of small bowel of the dog.American Journal of Physiology-Endocrinology and Metabolism, 1977
- SOMATOSTATIN INHIBITS THE RELEASE OF ACETYLCHOLINE INDUCED ELECTRICALLY IN THE MYENTERIC PLEXUSEndocrinology, 1976