Vasoactive intestinal polypeptide facilitates the late component of the 5-hydroxytryptamine-induced discharge in the cat superior cervical ganglion.
The intra-arterial administration of vasoactive intestinal polypeptide (VIP, 1-10 micrograms, i.a.) to the cat superior cervical ganglion facilitated or unmasked the late component but not the early component of the 5-hydroxytryptamine (5-HT, 0.5-50 micrograms, i.a.)-induced postganglionic discharge. The facilitation occurred in acutely and chronically decentralized ganglia. The early and late 5-HT discharges were blocked by MDL-72222, a 5-HT antagonist, but not by cholinergic antagonists. These data together with previous observations indicate that VIP selectively facilitates slow cholinergic and non-cholinergic excitatory mechanisms in autonomic ganglia.
D000818:Animals; D001285:Atropine / Q000494:pharmacology; D001338:Autonomic Fibers, Postganglionic / Q000187:drug effects / Q000502:physiology*; D002415:Cats; D005260:Female; D005728:Ganglia, Sympathetic / Q000187:drug effects / Q000502:physiology*; D018738:Hexamethonium; D006584:Hexamethonium Compounds / Q000494:pharmacology; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects; D012701:Serotonin / Q000502:physiology*; D012702:Serotonin Antagonists / Q000494:pharmacology; D014326:Tropanes / Q000494:pharmacology; D014660:Vasoactive Intestinal Peptide / Q000502:physiology*
D006584:Hexamethonium Compounds; D012702:Serotonin Antagonists; D014326:Tropanes; D012701:Serotonin; D014660:Vasoactive Intestinal Peptide; D018738:Hexamethonium; D001285:Atropine; C042253:bemesetron