The effect of pancuronium and gallamine on muscarinic transmission in the superior cervical ganglion.
Pancuronium enhanced contraction of the nictitating membrane elicited via ganglionic muscarinic pathways in the superior cervical ganglion of the cat. In order to elucidate this phenomenon, recordings of the superior cervical ganglion surface potential were made which demonstrated that pancuronium and gallamine reduced and haloperidol enhanced ganglionic hyperpolarization without significantly altering the ganglionic slow depolarization. Pancuronium reversed the effects produced by haloperidol, whereas the latter drug was unable to antagonize those induced by pancuronium. These results allow the speculation that pharmacologically distinct muscarinic receptors reside in sympathetic ganglia, one of which is susceptible to blockade by pancuronium or gallamine.
D000818:Animals; D002415:Cats; D004347:Drug Interactions; D005260:Female; D005703:Gallamine Triethiodide / Q000494:pharmacology*; D005727:Ganglia, Spinal / Q000187:drug effects*; D006220:Haloperidol / Q000494:pharmacology; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects; D009541:Nictitating Membrane / Q000187:drug effects; D010197:Pancuronium / Q000494:pharmacology*; D010275:Parasympathetic Nervous System / Q000187:drug effects*; D009435:Synaptic Transmission / Q000187:drug effects*
D006220:Haloperidol; D010197:Pancuronium; D005703:Gallamine Triethiodide