OBJECTIVETo observe the differences of the expression of Cx43 in rats' acupoints and sham-acupoint when needled blocks, and explore the relatively specificity of acupoints.

METHODTwenty Wistar rats were randomly divided into two groups: an acupuncture group and a control group, ten in each group. The rats in the control group were not treated and sacrificed directly to by air embolism; the rats in the acupuncture group were needled at "Neiguan (PC 6)", "Zusanli (ST 36)", "Dazhui (GV 14)" and "Guanyuan (CV 4)", Sham-acupoints were on 1 cm next to each of the above acupoints and "Yongquan (KI 1)" were needled by hand manipulation, retented needles for 30 min, then all the rats were sacrificed by air embolism. With the rats fixed, the tissue blocks at the acupoints and sham-acupoints were collected, then quick-frozen and cut into sections. The sections were stained by immunohistochemical method (Cx43).

RESULTSThe expression of the rats' Cx43 at the acupoints was significantly higher than that at the non-points in both groups (all P < 0.01). The expression of Cx43 at the acupoints in the acupuncture group was significantly higher than that in the control group (all P < 0.01).

CONCLUSIONThe expression of Cx43 at acupoints and non-points is significantly different, which indicates that the acupoints are actually existed and have relatively specificity.