OBJECTIVETo explore the material basis of conduction along meridian.

METHODSSixty SD rats(30 males,30 females) were randomly assigned into a normal group,an acupuncture group,a verapamil blocking group and a 0.9%NaCl blocking group(control group),15 rats in each one. Fluo 3-AM(calcium fluorescence probe) was injected at the observation part in femoral stomach meridian of foot-(meridian part) and the approaching femoral meridian part(non-meridian part) in the normal group and the acupuncture group,and then incubation was applied. In the verapamil blocking group,verapamil was injected at local meridian part and non-meridian part,and in the control group 0.9%NaCl was injected. Then Fluo 3-AM was injected at the meridian part and non-meridian part in the two groups,and incubation was implemented. Caimaging changes in cells were recorded for more than 20 min after injection of every part in each group respectively. After the above operations in the last three groups,acupuncture was used at "Zusanli"(ST 36) immediately,with electroacupuncture for one min,then Caimaging changes in cells at the meridian and non-meridian parts were recorded for more than 20 min.

RESULTSIn the normal group, Cafluorescence intensity at the meridian part was higher than that at the non-meridian part. In the acupuncture group,after acupuncture Cafluorescence intensity at the meridian part was obviously higher than before,but the change before and after acupuncture was not apparent at the non-meridian part. After verapamil blocking local calcium channel and acupuncture,the Cafluorescence of the meridian part did not strengthen,and the change of that before and after acupuncture at the non-meridian part was not obvious. In the control group,after injecting 0.9%NaCl at local part,Cafluorescence intensities of the meridian and non-meridian parts showed no obvious change,so was that before and after acupuncture.

CONCLUSIONSThe voltage-gated calcium channel at the meridian part is highly correlated with its tissue cells exciting conduction.