Wenjing Zhitong recipe exhibits potential anti-primary dysmenorrhea properties by inhibiting COX2 and PKC signaling pathway in rats induced by estradiol benzoate and oxytocin

Objective: To explore the effect and mechanism of action of the Wenjing Zhitong recipe（WZR） in primary dysmenorrhea（PD） treatment.Methods: Uterine contractions were induced by estradiol benzoate and oxytocin in a PD model and WZR was administrated. The rate of change in uterine contractility and the writhing test were used to evaluate the effects of WZR. The serum levels of prostaglandin F 2a (PGF 2a ) and prostaglandin E 2 （PGE 2 ）, and the activity of cyclooxygenase-2（COX2） were detected by enzyme-linked immunosorbent assay（ELISA）. The changes in phosphor-phospholipase C（pPLC/PLC）, phosphor-protein kinase C（pPKC/PKC）, and connexin 43（CX43） expression were detected using immunohistochemistry and western blot.Results: WZR significantly reduced the rate of change in uterine contractility and writhing times in the PD model. WZR treatment inhibited the enzymatic activity of COX2 and reduced the levels of PGF 2a ,PGF 2a /PGE2and COX2 in the PD model. WZR also significantly reduced the expression of pPLC/PLC, pPKC/PKC and CX43. Targeting the inhibition of COX2 activity, caffeic acid and 1-acetyl-β-carboline were validated as the active ingredients in WZR responsible for reducing uterine contractions.Conclusion: WZR attenuated PD by inhibiting COX2 activity, downregulating PGF 2a /PGE 2 expression, and inhibiting the PKC signaling pathway.