Analgesic Effect and Action Mechanisms of Wenjing Zhitong Prescription on Primary Dysmenorrhea / 中国实验方剂学杂志

Objective:To evaluate the analgesic effects of Wenjing Zhitong prescription （WZP） and explore its possible analgesic mechanisms so as to provide experimental basis for research and development of new Chinese medicine. Method:Analgesic effects of WZP were evaluated by observing the writhing latency and number in the writhing models which were induced by oxytocin in rats as well as those induced by acetic acid and prostaglandin E₁ （PGE₁）， respectively in mice. Effect of WZP on uterine contraction frequency， amplitude and activity were evaluated by observing the oxytocin-induced contraction of uterine smooth muscle in rats and rabbits <italic>in vivo</italic>. In the oxytocin-induced rat writhing models， the content of prostaglandin F₂<italic>_α</italic>（PGF₂<italic>_α</italic>） and prostaglandin E₂（PGE₂） in rat uterine tissues and the content of beta-endorphins （<italic>β</italic>-EP） in rat serum were detected by enzyme-linked immunosorbent assay （ELISA）. Expression of estrogen receptor （ER） and oxytocin receptor （OTR） in rat uterine were tested by Real-time polymerase chain reaction（Real-time PCR） method to investigate the possible molecular mechanism of WZP for its analgesic effect. Result:Results of analgesic effect showed that in oxytocin-induced rat writhing experiment， the number of writhing responses in both the WZP （1.5，3.0 g·kg^-1） group was lower than than in the model group （<italic>P</italic><0.05）. In acetic acid-induced mice writhing experiment， the latency of writhing response in WZP （6.0 g·kg^-1） group was significantly prolonged as compared with that in model group <italic>（P</italic><0.01）， and the number of writhing response was significantly reduced （<italic>P</italic><0.05）. In PGE₁-induced mice writhing model， the writhing number in WZP （1.5，3.0，6.0 g·kg^-1） groups was significantly lower than that in the model group （<italic>P</italic><0.05，<italic>P</italic><0.01）. Results of effect on uterine smooth muscle demonstrated that WZP （0.38，0.75，1.50 g·kg^-1） could significantly reduce the frequency of uterine smooth muscle contraction in rabbits （<italic>P</italic><0.05，<italic>P</italic><0.01）， WZP （0.75，1.50，3.00 g·kg^-1） could significantly reduce the contractile amplitude and activity of smooth muscle in the uterus of rats （<italic>P</italic><0.05）. Results of molecular mechanisms of analgesic effects showed that the WZP （0.75，1.50，3.00 g·kg^-1） significantly reduced the content of PGF₂<italic>_α</italic> and the ratio of PGF₂<italic>_α</italic> to PGE₂ in the uterine tissue of rats （<italic>P</italic><0.01）. In the WZP （3.00 g·kg^-1） group， the levels of <italic>β</italic>-EP in the serum of rats were significantly increased （<italic>P</italic><0.01）， and the levels of OTR in uterus of rats in the WZP （1.50，3.00 g·kg^-1） group were significantly decreased （<italic>P</italic><0.05）. Conclusion:Pharmacological studies demonstrated potent analgesic effect of WZP， and such analgesic effect were mediated by significantly inhibiting contraction of uterine smooth muscle， decreasing the contents of PGF₂<italic>_α </italic>and ratio of PGF₂<italic>_α</italic>/PGE₂， reducing OTR expression in uterine as well as increasing the amount of <italic>β</italic>-EP in serum.

Spray drying process of extract of Wenjing Zhitong Prescription based on mixture design experiment / 中国中药杂志

To improve the spray drying effect of extract of Wenjing Zhitong Prescription, this study takes the yield, hygroscopic property and the fluidity of dry powder as indexes to screen out auxiliary materials, and the proportion of the auxiliary materials was optimized based on the mixing design experiment; based on that, HPLC method was established for the determination of glycyrrhizin and 6-gingerol in spray powder, the yield of spray powder and the retention rate of the two index components were taken as indexes to further optimize the spray drying parameters. The finally selected auxiliary materials were light magnesium oxide, maltodextrin and silica, and regression equations of dry powder yield, moisture absorption rate, angle of rest with proportion of auxiliary materials were established, and the optimized proportion of auxiliary materials was dry paste-light magnesium oxide-maltodextrin-silica=0.5∶0.305∶0.145∶0.05; according to the optimized drying process parameters of Wenjing Zhitong Prescription, initial temperature was 60 ℃, air inlet temperature was 130 ℃, air flow rate was 35 m~3·h~(-1), atomizing pressure was 40 mm, and liquid inlet speed was 4.5 mL·min~(-1). Under these conditions, the dry powder yield was 90.28%, the retention rate of glycyrrhizin was 74.51%, and the retention rate of 6-gingerol was 72.10%. In this study, optimized auxiliary materials can improve the yield of spray drying and the property of spray powder, and the optimized processing conditions were good for retaining the unstable gingerol components, which can lay a foundation for the further preparation research of meridian warming and pain relieving prescriptions, and provide reference for extract of other traditional Chinese medicine extracts that are difficult to spray drying.