title: Serotonin or the Mucosa Do Not Mediate the Motor Effect of Allyl Isothiocyanate in the Guinea-Pig Small Intestine.
abstract: BACKGROUND
  Serotonin (5-hydroxytryptamine, 5-HT), originating from the enterochromaffin cells has been reported to mediate the contractile effect of the sensory stimulant and TRPA1 activator allyl isothiocyanate (AITC) in the guinea-pig small intestine [Nozawa et al: Proc Natl Acad Sci U S A 2009;106:3408-3413].
  
  
  CONCLUSIONS
  In the present experiments, the nerve-mediated contraction of this preparation due to AITC was not inhibited by a combination of methysergide (broad-spectrum 5-HT antagonist; 0.3 µmol/l), Y 25130 (azasetron, 5-HT3 receptor antagonist; 1 µmol/l) and SB 204070 (5-HT4 receptor antagonist; 2 µmol/l) or by 5-HT receptor desensitization, that is, pretreatments that practically abolished contractions of similar size in response to exogenous 5-HT, without causing nonspecific effects. AITC also contracted longitudinal muscle-myenteric plexus preparations, an effect also fully resistant to the combination of 5-HT receptor antagonists. The pharmacology of AITC in strip preparations matched that in the whole ileum. Key Messages: It is concluded that neither endogenous 5-HT nor the gut mucosa contributes to the excitatory effect of AITC in the guinea-pig small intestine. The combination of 5-HT antagonists elaborated is suitable for studying the possible involvement of 5-HT in motor responses of the guinea-pig intestine.
authors.affiliation: Department of Pharmacology and Pharmacotherapy, University Medical School of Pecs, Pecs, Hungary.
authors.forename: Zsolt I
authors.initials: ZI
authors.lastname: Sandor
authors.forename: Timea
authors.initials: T
authors.lastname: Bencsik
authors.forename: Andras
authors.initials: A
authors.lastname: Dekany
authors.forename: Lorand
authors.initials: L
authors.lastname: Bartho
mesh_terms: D000818:Animals; D005260:Female; D005769:Gastrointestinal Motility / Q000187:drug effects* / Q000502:physiology; D006168:Guinea Pigs; D007413:Intestinal Mucosa / Q000187:drug effects* / Q000502:physiology; D007421:Intestine, Small / Q000187:drug effects* / Q000502:physiology; D017879:Isothiocyanates / Q000494:pharmacology*; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects* / Q000502:physiology; D009924:Organ Culture Techniques; D012701:Serotonin / Q000502:physiology; D012702:Serotonin Antagonists / Q000494:pharmacology
chemical_list: D017879:Isothiocyanates; D012702:Serotonin Antagonists; D012701:Serotonin; C004471:allyl isothiocyanate