Relaxant Effect and Underlying Mechanisms of Evodiamine on Isolated Myometrium of Rats / 中国药师

ABSTRACT

Objective: To study the relaxant effect and underlying mechanisms of evodiamine on isolated myometrium of rats. Methods:Prostaglandin F2α( PGF2α) was used to induce isolated myometrium contraction. The relaxant effect of evodiamine and the influence of capsazepine (an antagonist of transient receptor potential cation channel, subfamily V, member 1, TRPV1), U73122 (an antagonist of phospholipase Cβ,PLCβ) and W-7 ( an antagonist of camodulin, CaM) on the relaxant effect of evodiamine on myometri-um were observed respectively by biological function experiments. The median effective concentration ( EC50 ) was analyzed by non-line-ar various slope regressions using Prism-5. 01 software. Results:Evodiamine showed concentration-dependent relaxant effect on PGF2α-induced myometrium contraction with the EC50of 9.56 ×10 -9mol·L-1. Incubation with capsazepine (6.30 ×10 -11 mol·L-1), U73122 (2. 57 × 10 -11 mol·L-1 ) and W-7 (5. 65 × 10 -13 mol·L-1 ) markedly increased the relaxant effect of evodiamine, the EC50 of evodiamine decreased and dose-effect curves left shifted. The order of EC50 was as follows W-7- evodiamine (8. 88 × 10 -15 mol· L-1) < capsazepine-evodiamine (7.35 ×10 -13 mol·L-1) < U73122-evodiamine (1.95 ×10 -12mol·L-1). Conclusion: Evodia-mine can inhibit myometrium contraction induced by PGF2αobviously, and the mechanisms are probably related to TRPV1, PLCβand CaM.