title: Olopatadine attenuates the enhancement of capsaicin-evoked substance P release by bradykinin from cultured dorsal root ganglion neurons.
abstract: Olopatadine, a second-generation antihistamine, has recently been suggested to have an inhibitory effect on the tachykinin release from guinea-pig tracheobronchial smooth muscle preparation. In the present study, using a highly sensitive radioimmunoassay for substance P, we observed that olopatadine attenuated the enhancement of capsaicin-induced substance P release by bradykinin with an IC(50) value of 12.5 microM, without any inhibitory effect on the substance P release induced by capsaicin, potassium or bradykinin from cultured dorsal root ganglion neurons. These data suggest that olopatadine may therefore be involved in the bradykinin-induced sensitization of the transient receptor potential vanilloid 1 in cultured dorsal root ganglion neurons.
authors.affiliation: Department of Pharmacology, Graduate School of Biomedical Sciences, Hiroshima University, Kasumi 1-2-3, Minami-ku, Hiroshima 734-8553, Japan.
authors.forename: He-Bin
authors.initials: HB
authors.lastname: Tang
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Nakata
mesh_terms: D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology; D001920:Bradykinin / Q000494:pharmacology*; D002211:Capsaicin / Q000494:pharmacology*; D002478:Cells, Cultured; D003990:Dibenzoxepins / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005727:Ganglia, Spinal / Q000166:cytology; D009474:Neurons / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D000069605:Olopatadine Hydrochloride; D011188:Potassium / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D013373:Substance P / Q000378:metabolism*; D013997:Time Factors
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D003990:Dibenzoxepins; D000069605:Olopatadine Hydrochloride; D013373:Substance P; D011188:Potassium; D002211:Capsaicin; D001920:Bradykinin