Possible mechanism of ruthenium red antagonism of capsaicin-induced action in the isolated guinea pig ileum.
Ruthenium red (3-5 microM) antagonism of the inhibitory effect of capsaicin (1 microM) on the contractile response to mesenteric nerve stimulation in the presence of hexamethonium (50 microM) and guanethidine (2 microM) was reversed significantly by sialic acid (2 mM) or neuraminidase (0.1 U/ml). These results suggested that ruthenium red at low concentrations inhibits the capsaicin-induced desensitization of activated Ca2+ influx into sensory nerves at least in part by binding to sialic acid residues.
Takaki
M
M
Department of Physiology, Okayama University Medical School, Japan.
Nakayama
S
S
Suga
H
H
D000818:Animals; D002211:Capsaicin / Q000008:administration & dosage / Q000037:antagonists & inhibitors*; D005260:Female; D006145:Guanethidine / Q000008:administration & dosage / Q000494:pharmacology; D006168:Guinea Pigs; D018738:Hexamethonium; D006584:Hexamethonium Compounds / Q000008:administration & dosage / Q000494:pharmacology; D007082:Ileum; D066298:In Vitro Techniques; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D019158:N-Acetylneuraminic Acid; D012430:Ruthenium Red / Q000008:administration & dosage / Q000494:pharmacology*; D012794:Sialic Acids / Q000008:administration & dosage / Q000494:pharmacology
D006584:Hexamethonium Compounds; D012794:Sialic Acids; D012430:Ruthenium Red; D018738:Hexamethonium; D019158:N-Acetylneuraminic Acid; D002211:Capsaicin; D006145:Guanethidine