Zaltoprofen

Zaltoprofen binds to specific sites on the protein of the bradykinin B2 receptor, hence we have examined the effect of zaltoprofen on bradykinin-induced responses of adult DRG neurons to investigate possible interaction sites. Zaltoprofen most potently inhibits bradykinin-enhancement of capsaicin-induced Ca²⁺ uptake into DRG neurons. Zaltoprofen also significantly inhibits bradykinin-induced 12-lipoxygenase (12-LOX) activity and the slow bradykinin-induced onset of substance P release from DRG neurons. ^[1] Zaltoprofen produces an analgesic action on bradykinin-induced nociceptive responses by blocking the B(2) receptor-mediated pathway in the primary sensory neurons. Zaltoprofen completely inhibits the bradykinin-induced increase of [Ca(2+)](i), which is inhibited by B(2) antagonist D-Arg-[Hyp(3), Thi(5,8), D-Phe(7)]-bradykinin, but not by B(1) antagonist. ^[2] Zaltoprofen at 1nmol shows strong analgesic action on BK (i.pl.)-induced nociceptive flexor responses, whereas loxoprofen or its active metabolite loxoprofen-SRS does not. Zaltoprofen also inhibits the nociception induced by [Tyr8]-BK, a specific agonist of B2-type BK receptor, but does not affect the nociception by [Lys-des-Arg9]-BK, a specific agonist of B1-type BK receptor. ^[3] Zaltoprofen is a non-steroidal anti-inflammatory drug (NSAID) causes potent inhibition of cyclooxygenase-2 with fewer side effects on the gastrointestinal tract.^[4]

Zaltoprofen improves the loss in body weight in both Con A-treated mice and carbon tetrachloride-treated rats. ^[4] Zaltoprofen (10 mg/kg) administrated at 8 h after Con A treatment is found to inhibit the Con A-induced reduction in body weight. Zaltoprofen (10 mg/kg) combined with Con A results in four times greater food intake than that in mice treated with only Con A. ^[5]