title: Enhancement of 5-hydroxytryptamine-induced contraction of the guinea pig ileum by a new sulfur compound, tripropylsulfonium bromide.
abstract: In the presence of tripropylsulfonium bromide (TPS) (1 X 10(-4) g/ml), a new compound, the phasic contraction of the isolated guinea pig ileum to 5-hydroxytryptamine (5-HT) (5 X 10(-7) g/ml) was consistently enhanced ("TPS effect"). TPS alone increased moderatley the spontaneous movement of the ileum. When the contraction height was calculated as the percentage of that to 5-HT alone, such was observed in the "TPS effect" to be 167.1 +/- 3.6% (mean +/- S.E., n = 80). TPS did not enhance the contraction due to acetylcholine or histamine. The "TPS effect" remained unaffected in the presence of dibenzyline (1 X 10(-7) g/ml), was abolished by morphine(1 X 10(-6) g/ml), tetrodotoxin (2 X 10(-8) g/ml) adenosine (3 X 10(-6) g/ml) and atropine (1 X 10(-7) g/ml) and was not observed under anoxic conditions. Eserine (1 X 10(-8) g/ml) strengthened the "TPS effect" markedly. It is concluded that this effect may be the result of the potentiating effect of TPS on the action of 5-HT through the M receptors, possibly by the facilitation of the acetylcholine-liberation from the nervous tissue.
mesh_terms: D000109:Acetylcholine / Q000378:metabolism / Q000494:pharmacology; D000818:Animals; D001285:Atropine / Q000494:pharmacology; D004357:Drug Synergism; D005260:Female; D006168:Guinea Pigs; D006632:Histamine / Q000494:pharmacology; D007082:Ileum; D066298:In Vitro Techniques; D008297:Male; D009020:Morphine / Q000494:pharmacology; D009119:Muscle Contraction / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects*; D009411:Nerve Endings / Q000378:metabolism; D009861:Onium Compounds / Q000494:pharmacology*; D010830:Physostigmine / Q000494:pharmacology; D012701:Serotonin / Q000494:pharmacology*; D013452:Sulfonium Compounds / Q000037:antagonists & inhibitors / Q000494:pharmacology*
chemical_list: D009861:Onium Compounds; D013452:Sulfonium Compounds; D012701:Serotonin; C018166:tripropylsulfonium bromide; D009020:Morphine; D001285:Atropine; D006632:Histamine; D010830:Physostigmine; D000109:Acetylcholine