A phorbol ester and A23187 act synergistically to release acetylcholine from the guinea pig ileum.
Electrical stimulation of guinea pig ileum preloaded with [3H]choline provokes the release of [3H]acetylcholine (ACh) in a Ca2+-dependent manner. This release was markedly increased by the tumor-promoting phorbol ester, 12-O-tetradecanoylphorbol 13-acetate (TPA). The combination of the ionophore A23187 and TPA produced the release of [3H]ACh up to a level equal to or exceeding a maximal response induced by electrical stimulation. A23187 alone gave only a minor response and TPA alone had no apparent effect on the [3H]ACh release. Thus, protein kinase C probably plays a role in cell surface signal transduction related to the release of transmitters from nerve endings.
D000109:Acetylcholine / Q000378:metabolism*; D000818:Animals; D000001:Calcimycin / Q000494:pharmacology*; D002118:Calcium / Q000494:pharmacology; D002794:Choline / Q000378:metabolism; D004357:Drug Synergism; D004558:Electric Stimulation; D005260:Female; D006168:Guinea Pigs; D007082:Ileum / Q000187:drug effects / Q000378:metabolism*; D007700:Kinetics; D008297:Male; D010704:Phorbols / Q000494:pharmacology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*; D014316:Tritium
D010704:Phorbols; D014316:Tritium; D000001:Calcimycin; D002794:Choline; D000109:Acetylcholine; D013755:Tetradecanoylphorbol Acetate; D002118:Calcium