Objective To observe the effects of electroacupuncture(EA)on gastrointestinal motility and the ultrastructure of interstitial cells of Cajal(ICC)and the expressions of c-kit receptor protein and stem cell factor(SCF)mRNA in diabetic gastroparesis(DGP)rats

so as to explore its mechanism.Methods Fifty SD rats were randomly divided into normal

model

acupoint

non-acupoint and metoclopramide groups(n=10 rats/group).DGP model was established by intraperitoneal injection of streptozotocin(STZ

2%)

and raised with high-sugar high-fat diet irregularly.EA(sparse-dense

10 Hz/50 Hz

2 mA

20 min)was applied at"Zusanli"(ST 36)

"Liangmen"(ST 21)and"Sanyinjiao"(SP 6)

and the corresponding non-acupoints of the 3 acupoints

daily for 15 days.The rats in metoclopramide group received intragastric administration of metoclopramide(1.7%

1 mL/100 g)for 15 days

once a day.Blood sugar was determined with One Touch blood glucose test paper.The gastric emptying rate(GER)and the intestinal propulsion rate(IPR)were measured by intragastric phenol red.The ultrastructure of ICC was detected by transmission electron microscopy.The expression levels of c-kit receptor protein and SCF mRNA of gastric antrum were examined respectively by Western blot and RT-PCR.Results Compared with the normal group

the blood glucose significantly increased in the model group(P<0.01)

while the GER

IRP and the expression level of SCF mRNA in the gastric antrum significantly decreased(P<0.01)

and the ultrastructure of ICC appeared apoptosis-like changes.The blood glucose of the EA group was obviously decreased compared with that of the model group(P <0.05);the GER and IRP significantly increased(P<0.05

P<0.01);the expression level of SCF mRNA increased(P<0.01)

the number of ICC increased and its ultrastructure was repaired.There was some relief on ICC ultrastructure in the acupoint group compared with that in the nonacupoint group;and SCF mRNA increased(P<0.05).There was no significant difference on c-kit receptor expression among all the modeling groups(P>0.05).Conclusion EA at ST 36

etc.can regulate the blood glucose and improve gastrointestinal emptying in DGP rats.The mechanism may be related to up-regulating SCF mRNA

repairing ICC ultrastructure

restoring the pacing function

and improving gastrointestinal motility.