The release of 5-hydroxytryptamine from the rat stomach in vitro.
1. 5-HT was released into the lumen of the intact isolated rat stomach and into the bath fluid surrounding a preparation of the body and antrum stretched mechanically.2. Release of 5-HT increased when the pressure inside the intact stomach was raised or when the body/antrum preparation was stretched.3. This increased release was not prevented by hexamethonium, atropine, hyoscine or procaine, and was probably due to distortion of cells containing 5-HT.4. During periods of peristalsis induced by transmural stimulation the pharmacological activity of the fluid in the stomach was usually increased owing to a greater release of 5-HT and also to the release of an unidentified substance.5. In reserpine-treated rats, 5-HT was released into the stomach but transmural stimulation did not produce true peristalsis and only rhythmic contractions occurred.6. Peristalsis was seldom reduced by methysergide, and it is concluded that 5-HT is not essential for gastric peristalsis in the rat.
D000818:Animals; D001285:Atropine / Q000494:pharmacology; D005753:Gastric Mucosa / Q000378:metabolism*; D005769:Gastrointestinal Motility; D006584:Hexamethonium Compounds / Q000494:pharmacology; D066298:In Vitro Techniques; D008784:Methysergide / Q000494:pharmacology; D011312:Pressure; D011343:Procaine / Q000494:pharmacology; D051381:Rats; D012110:Reserpine / Q000494:pharmacology; D012601:Scopolamine / Q000494:pharmacology; D012701:Serotonin / Q000378:metabolism*
D006584:Hexamethonium Compounds; D012701:Serotonin; D011343:Procaine; D001285:Atropine; D012110:Reserpine; D012601:Scopolamine; D008784:Methysergide