Objective: To probe into the expression of connexin(Cx)43 in rat's "Zusanli"(ST 36) and its possible relationship with acupoint and meridian Methods: Twenty SD rats were evenly randomized into control(non-acupoint) group and electroacupuncture(EA) group.Right "Zusanli"(ST 36) and non-acupoint(0.5 mm lateral to ST 36) were punctured and stimulated electrically with dense-sparse pulses

frequency of 4 Hz

strength of 1-3 V and duration of 30 min.At the end of experiments

the rats were anesthetized with 1% pentobarbital and perfused transcardially with 4% paraformaldehyde.Then

the skin and muscle tissues(3 mm × 6 mm × 5 mm) of ST 36 and non-acupoint regions on the EA and non-EA sides were taken to be cut into sections and stained with propidium iodide(PI) and FTTC(fluorescein isothiocyanate) conjugated antibody respectively.Laser scanning confocal microscope (LSCM) was used to detect Cx43 expression quantity.Results: Cx43 expression was found mainly in rat's skin epithelia and mast cells of the subcutaneous fascia layer.In control group the expression of Cx43 in acupoint area was distinctly higher than that in non-acupoint area(P<0.01).In EA group

the expression of Cx43 in acupoint area increased obviously in comparison with that in the acupoint area on the non-EA side and in non-acupoint area on the EA side(P<0.01).No significant differences were found among non-acupoints of control group

and non-acupoint on EA and non-EA sides(P>0.05).Conclusion: EA can effectively raise Cx43 expression in the skin and muscles in the acupoint area

suggesting that connexin and gap junction in the acupoint area possibly play an important role in the functional activities of meridian.