Fentanyl and pethidine are antagonists on muscarinic receptors in guinea-pig ileum
- Resource Type
- Authors
- J. Setekleiv; O. Hustveit
- Source
- Acta Anaesthesiologica Scandinavica. 37:541-544
- Subject
- Male
Agonist
Meperidine
medicine.drug_class
Guinea Pigs
Muscarinic Antagonists
Pharmacology
Binding, Competitive
Parasympatholytic
Fentanyl
Guinea pig
Ileum
Muscarine
Muscarinic acetylcholine receptor
Anticholinergic
Animals
Medicine
Dose-Response Relationship, Drug
business.industry
Antagonist
General Medicine
Pethidine
Anesthesiology and Pain Medicine
Carbachol
business
Muscle Contraction
medicine.drug
- Language
- ISSN
- 1399-6576
0001-5172
In order to evaluate the anticholinergic effect of fentanyl and pethidine, the influence of these drugs on the cumulative dose-response curves of carbacholine on the guinea-pig ileum has been investigated. Fentanyl and pethidine displaced the dose-response curve for carbacholine to the right in a parallel fashion, indicating competitive antagonism. Dissociation constants determined by an agonist EC versus antagonist plot were 0.22 mumol/l for fentanyl and 1.4 mumol/l for pethidine. It is concluded that during high-dose fentanyl anaesthesia, fentanyl may bind to muscarinic receptors and thereby produce a central anticholinergic syndrome. An additional finding was that the maximal response to carbacholine increased significantly when combined with pethidine.