Objective To observe the alternations of local mast cells(MCs) in the number and functional activities after electroacupuncture(EA) and injection of stem cell factor(SCF) antibody into "Weishu"(BL 21) and "Zusanli"(ST 36) in rats.Methods Thirty Wistar rats were randomly assigned to normal

EA

and EA+SCF antibody injection(EA-ABI) groups(n=10).EA was applied to the left "Weishu"(BL 21) and "Zusanli"(ST 36) for 25 min.For rats of EA+ABI group

SCF-AB(1∶200

0.1 mL) was respectively injected into BL 21 and ST 36

following by EA.The tissues around the two acupoints areas were sampled to be stained with acetylcholine esterase(AchE) and toluidine blue(TB)

respectively.The counts and degranulation ratio of MCs in the acupoint region were recorded and observed under microscope.Results In comparison with the normal group

MCs count was increased significantly in the EA of "Weishu"(BL 21) group(P<0.05)

mildly in the EA of "Zusanli"(ST 36) group(P>0.05)

and downregulated considerably in both EA-ABI-BL 21 and EA-ABI-ST 36 groups(P<0.05).Compared with the normal group

the degranulation ratio of MCs was increased significantly in EA-BL 21

EA-ST 36

EA-ABI-BL 21 and EA-ABI-ST 36 groups(P<0.05).No significant differences were found between EA-BL 21 and EA-ABI-BL 21 groups

and between EA-ST 36 and EA-ABI-ST 36 groups in the degranulation ratios(P>0.05).Conclusion Local injection of SCF antibody in BL 21 and ST 36 can significantly suppress EA-induced increase of the number and degranulation ratio of local subcutaneous MCs in rats

suggesting that SCF is an important factor affecting the activity and recruitment of MCs around the acupoint during EA.