Mediation of neurogenic ion transport by acetylcholine, prostanoids and 5-hydroxytryptamine in porcine ileum.
Enteric neural activity modulates active transepithelial ion transport in the intestine. We investigated the neural circuits mediating neurogenic secretion in mucosal explants from porcine ileum. Transmural electrical stimulation increased short-circuit current, a measure of active ion transport, by 35+/-2 microA/cm2. The neuronal Na+ channel blocker saxitoxin, the muscarinic cholinergic receptor antagonist atropine, the 5-hydroxytryptamine3 receptor antagonist tropisetron, and the cyclooxygenase inhibitor indomethacin inhibited this response. In addition, tropisetron inhibited the atropine-resistant portion of the response, and both atropine and indomethacin attenuated the saxitoxin-resistant component. Neurogenic secretion in porcine ileum appears to be mediated by tryptaminergic and prostanoid-sensitive cholinergic pathways.
Townsend
DeWayne
D
Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, Minnesota, MN 55108-6010, USA.
Casey
Melissa A
MA
Brown
David R
DR
D015126:8,11,14-Eicosatrienoic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D000109:Acetylcholine / Q000494:pharmacology*; D000818:Animals; D001285:Atropine / Q000494:pharmacology; D004558:Electric Stimulation; D005260:Female; D007082:Ileum / Q000187:drug effects* / Q000294:innervation / Q000378:metabolism; D066298:In Vitro Techniques; D007211:Indoles / Q000494:pharmacology; D007213:Indomethacin / Q000494:pharmacology; D007413:Intestinal Mucosa / Q000187:drug effects / Q000294:innervation / Q000378:metabolism; D017136:Ion Transport / Q000187:drug effects; D008297:Male; D011453:Prostaglandins / Q000494:pharmacology*; D012530:Saxitoxin / Q000494:pharmacology; D012701:Serotonin / Q000494:pharmacology*; D018490:Serotonin Agents / Q000494:pharmacology; D012702:Serotonin Antagonists / Q000494:pharmacology; D013552:Swine; D000077526:Tropisetron; D014665:Vasodilator Agents / Q000494:pharmacology
D007211:Indoles; D011453:Prostaglandins; D018490:Serotonin Agents; D012702:Serotonin Antagonists; D014665:Vasodilator Agents; D012701:Serotonin; D012530:Saxitoxin; C025421:eicosa-8,11,14-trien-5-ynoic acid; D000077526:Tropisetron; D001285:Atropine; D015126:8,11,14-Eicosatrienoic Acid; D000109:Acetylcholine; D007213:Indomethacin