Vasoactive intestinal polypeptide facilitates muscarinic transmission in mammalian sympathetic ganglia.
Vasoactive intestinal polypeptide (VIP) in the concentration of 1 microM or less markedly and selectively increased the amplitude and duration of the muscarinic slow excitatory postsynaptic potential (EPSP) without appreciably affecting the nicotinic fast EPSP or the non-cholinergic EPSP of guinea pig inferior mesenteric ganglion cells. The membrane depolarization evoked by the muscarinic agonist, acetyl-beta-methylcholine in these neurons was similarly enhanced by VIP. Our results suggest that the peptide may be a neuromodulator effective in enhancing the sensitivity of postsynaptic muscarinic receptors to acetylcholine in the vertebrate sympathetic ganglia.
D000109:Acetylcholine / Q000502:physiology; D000818:Animals; D005728:Ganglia, Sympathetic / Q000187:drug effects* / Q000502:physiology; D006168:Guinea Pigs; D018377:Neurotransmitter Agents; D011976:Receptors, Muscarinic / Q000187:drug effects*; D013268:Stimulation, Chemical; D009435:Synaptic Transmission / Q000187:drug effects*; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology* / Q000502:physiology
D018377:Neurotransmitter Agents; D011976:Receptors, Muscarinic; D014660:Vasoactive Intestinal Peptide; D000109:Acetylcholine