Effect of Genkwa Flos on Transient Receptor Potential Vanilloid 1 of Thermosensitive Channel / 中国实验方剂学杂志

ABSTRACT

Objective:To study the effect of Genkwa Flos on the thermosensitive channel, transient receptor potential vanilloid 1 (TRPV1) by electrophysiological whole cell patch clamp technique and animal behavior experiment, in order to explore its mechanism. Method:The whole-cell patch clamp technique was used to measure transmembrane currents induced by 75%ethanol extract from different concentrations of Genkwa Flos in HEK293 cells that expressed human TRPV1.TRPV1 specific antagonist capsaicin was used to observe whether it could inhibit the transmembrane current induced by Genkwa Flos. Totally 30 C57BL/6 mice were taken for behavioral detection, and divided into blank group (6 mice), high-dose group (6 mice), medium-dose group (6 mice), low-dose group (6 mice) and ibuprofen positive control group (6 mice). Genkwa Flos treatment group was given low dose (0.195 g·kg-1·d-1), medium dose (0.39 g·kg-1·d-1) and high dose (0.78 g·kg-1·d-1) by gavage. One hour later, the changes of behavioral latency of cold pain and hot pain in mice were observed in cold plate at (0±2)℃ and hot plate at (55±1)℃. Result:Whole cell patch clamp experiment showed that 75%ethanol extract of Genkwa Flos in hTRPV1/HEK293 cells could activate TRPV1 channel to generate obvious transmembrane current, which was similar with that generated by the known TRPV1 agonist capsaicin in current density and current-voltage relationship. The dose-effect experiments showed that compared with extracellular fluid, 10 g·L-1 ethanol extract of Genkwa Flos could activate hTRPV1/HEK293 cells to induce significant transmembrane current (P-1 ethanol extract of Genkwa Flos was more than 3 g·L-1(P-1 ethanol extract of Genkwa Flos. In the experiment of cold plate and hot plate in mice, there was a dose-effect relationship between the latencies of cold pain behavior and hot pain behavior in mice prolonged by Genkwa Flos. In the experiment of cold plate, compared with the blank group, the cold pain behavior latency of mice in the medium-dose group was significantly prolonged (PPPPPConclusion:More than one TRPV1 agonist was included in 75%ethanol extract of Genkwa Flos. The warm, analgesic and anti-inflammatory effects of Genkwa Flos may be a series of effects after activation of TRPV1.