Capsaicin selectively reduces airway responses to histamine, substance P and vagal stimulation.
Airway responsiveness to histamine, substance P, methacholine and bilateral electrical vagal stimulation was assessed in capsaicin-treated and control guinea pigs. In animals treated with capsaicin (50 mg/kg s.c.) 7 days before experiments, airway responsiveness to histamine, substance P and vagal stimulation was significantly reduced but responsiveness to methacholine was unchanged. The findings suggest that histamine and substance P, but not methacholine, require capsaicin-sensitive sensory afferent nerves for part of their actions.
Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Canada.
D F
DF
Biggs
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Ladenius
D000818:Animals; D002211:Capsaicin / Q000494:pharmacology*; D004558:Electric Stimulation; D005260:Female; D006168:Guinea Pigs; D006632:Histamine / Q000494:pharmacology*; D006633:Histamine Antagonists; D066298:In Vitro Techniques; D008688:Methacholine Compounds / Q000494:pharmacology; D012137:Respiratory System / Q000187:drug effects*; D013373:Substance P / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D014630:Vagus Nerve / Q000502:physiology*
D006633:Histamine Antagonists; D008688:Methacholine Compounds; D013373:Substance P; D006632:Histamine; D002211:Capsaicin