Effects of adrenaline, dopamine, serotonin, and different cholinergic agents on smooth muscle preparations from the ansa proximalis coli in cattle: studies in vitro.
The effects of adrenaline, dopamine, serotonin, and different cholinergic agents on isolated muscle strips from the ansa proximalis coli in cattle were studied. Adrenaline (5 x 10(-5) mol/l) evoked a relaxing effect (p < 0.05) on longitudinal and circular muscle strips, mediated via beta- and alpha 1-receptors respectively. High concentration of dopamine (5 x 10(-4) mol/l) caused a non-significant inhibitory effect on longitudinal smooth muscles, which was probably mediated by beta- and not by dopamine-receptors. Serotonin (5 x 10(-5) mol/l) and cisapride (75 x 10(-6) mol/l) had no effect. Carbachol (2 or 10 x 10(-6) mol/l) and bethanechol (5 or 10 x 10(-5) mol/l) caused a dose-dependent (p < 0.05) contraction of both smooth muscle types. This excitatory effect was inhibited (p < 0.05) by metoclopramide (1 x 10(-4) mol/l), as well as the muscarinic agents RS-86 (5 x 10(-5) mol/l) and CGP-37,218 (37.5 or 75 x 10(-6) mol/l).
Department of Veterinary Surgery, University of Zürich, Switzerland.
A
A
Steiner
M
M
Denac
U
U
Ballinari
D000818:Animals; D002417:Cattle / Q000502:physiology*; D003106:Colon / Q000187:drug effects* / Q000502:physiology; D046508:Culture Techniques; D004298:Dopamine / Q000494:pharmacology; D004837:Epinephrine / Q000494:pharmacology; D005260:Female; D008297:Male; D009130:Muscle, Smooth / Q000187:drug effects*; D018377:Neurotransmitter Agents / Q000494:pharmacology*; D010277:Parasympathomimetics / Q000494:pharmacology*; D012701:Serotonin / Q000494:pharmacology
D018377:Neurotransmitter Agents; D010277:Parasympathomimetics; D012701:Serotonin; D004298:Dopamine; D004837:Epinephrine