Objective To observe the effect of acupuncture on dysmenorrhea response of Cx43 knock out mice.Methods Two months old heterozygote [Cx43(+/-)] type and wild type [Cx43(+/+)] female mice(20 mice/type)were allocated into normal group

model group

acupuncture group and Yimucao Gao(Extractum Leonuri Inspissatum)group randomly.Dysmenorrheal model was established by feeding the mouse with diethylstilbestrol(2 mg/g)once daily for 12 days.Ocytocin(i.p.2 U/kg)was injected on the 12th day 1 h later after the feeding.Acupuncture of "Sanyinjiao"(SP 6)and "Diji"(SP 8)was given to mice of acupuncture group

once daily for 5 days from the 7th day on after modeling.The latency of body-writhing and the writhing number were measured.Ocytocin receptor(Oct-R)mRNA and vasopressin receptor(Vas-R)mRNA expression in the uterus tissue was detected by using reverse transcription polymerase chain reaction(RT-PCR)technique

and Oct-R expression was detected with immunohistochemistry after fixating and sectioning the uterus tissue.Results In comparison with their individual normal group

the latency of body-writhing of model groups in Cx43(+/+)and Cx43(+/-)mice shortened considerably

while the writhing number increased significantly(P<0.01).Compared with the corresponding model group

the writhing latencies of acupuncture and Yimucao Gao groups in Cx43(+/+)mice and that of Yimucao Gao group in Cx43(+/-)mice increased remarkably

and the writhing numbers of acupuncture and Yimucao Gao groups in Cx43(+/+)mice and that of Yimucao Gao group in Cx43(+/-)mice reduced markedly(P<0.05).In Cx43(+/+)and Cx43(+/-)mice

compared with their individual normal group

Oct-R and Vas-R mRNA expressions and Oct-R expression in model group were upregulated obviously(P<0.05).Compared with the corresponding model group

Oct-R and Vas-R mRNA expressions and Oct-R expression of acupuncture and Yimucao Gao groups in Cx43(+/+)mice

and those of Yimucao Gao group in Cx43(+/-)mice were down-regula-ted significantly(P<0.05).No significant differences were found between acupuncture and corresponding model groups in Cx43 ted significantly(P<0.05).No significant differences were found between acupuncture and corresponding model groups in Cx43(+/-)mice in the above-mentioned indexes(P>0.05).Conclusion Acupuncture can inhibit diethylstilbestrol +ocytocin induced body writhing response in Cx43(+/+)mice rather than in Cx43(+/-)mice

which is closely related to its effects in down-regulating Oct-R mRNA

Vas-R mRNA and Oct-R expression.