title: Ruthenium red prevents capsaicin-induced neurotoxic action on sensory fibers of the guinea pig ileum.
abstract: Capsaicin, a neurotoxin which impairs some primary afferent nerve fibers, was locally applied to the mesenteric nerve trunks of adult guinea pigs. The effect of capsaicin was studied on contractile responses of the ileum to mesenteric nerve stimulation (20 Hz). Exposure of the mesenteric nerve to capsaicin (1 microM) irreversibly abolished the contractile response to mesenteric nerve stimulation, without influencing the resting tension and spontaneous motility of the ileum. However, if the mesenteric nerve had been incubated in a Ca-free medium containing EGTA (0.1 mM) or pretreated with Ruthenium red (10 microM), capsaicin only partially inhibited (about 30%), but did not abolish, the contractile response to the mesenteric nerve stimulation, thus indicating protection from desensitization.
authors: Department of Physiology, Okayama University Medical School, Japan.
authors: J G
authors: JG
authors: Jin
authors: M
authors: M
authors: Takaki
authors: S
authors: S
authors: Nakayama
mesh_terms: D000818:Animals; D002211:Capsaicin / Q000494:pharmacology*; D005260:Female; D006168:Guinea Pigs; D007082:Ileum / Q000187:drug effects / Q000294:innervation*; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D009475:Neurons, Afferent / Q000187:drug effects* / Q000502:physiology; D009498:Neurotoxins / Q000494:pharmacology*; D012428:Ruthenium / Q000494:pharmacology*; D012430:Ruthenium Red / Q000494:pharmacology*
chemical_list: D009498:Neurotoxins; D012430:Ruthenium Red; D012428:Ruthenium; D002211:Capsaicin