Phorbol esters induce retrograde myoelectric activity in rabbit ileum in vivo.
We demonstrated a unique myoelectric response to phorbol esters and a diacylglycerol, 1-oleoyl-2-acetyl-snglycerol, in rabbit ileal loops. This retrograde activity, the orad migrating complex (OMC), was devoid of slow-wave distortion or alterations in slow-wave frequency. The OMC was not inhibited by the cyclooxygenase inhibitor indomethacin or enhanced by addition of the calcium ionophore A23187. The OMC occurred after 4 beta-phorbol 12-myristate 13-acetate, a phorbol ester known to activate protein kinase C, and after 4 alpha-phorbol 12,13-didecanoate, one that does not. Therefore, these studies provide initial evidence that the myoelectric activity induced by phorbol esters and a diacylglycerol is most likely in addition to the activation of protein kinase C.
Davis
R H
RH
Department of Medicine, University of Florida, Gainesville 32610.
Mathias
J R
JR
D000818:Animals; D000001:Calcimycin / Q000494:pharmacology; D004075:Diglycerides / Q000494:pharmacology; D004553:Electric Conductivity; D004594:Electrophysiology / Q000379:methods; D007082:Ileum / Q000187:drug effects / Q000502:physiology*; D007213:Indomethacin / Q000494:pharmacology; D008297:Male; D009130:Muscle, Smooth / Q000187:drug effects / Q000502:physiology*; D010703:Phorbol Esters / Q000494:pharmacology*; D011817:Rabbits; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D004075:Diglycerides; D010703:Phorbol Esters; D000001:Calcimycin; C038237:1-oleoyl-2-acetylglycerol; D013755:Tetradecanoylphorbol Acetate; D007213:Indomethacin