OBJECTIVETo explore the effects and action mechanism of electroacupuncture (EA) on Parkinson's disease (PD).

METHODSForty-eight healthy male SD rats were randomly divided into a normal group, a sham operation group, a model group and an EA group, 12 rats in each one. Rats in the model group and EA group were treated with subcutaneous injection of rotenone (1mg/kg, dissolved in dimethyl sulfoxide and 0. 9 % normal saline) on neck and back for 40 days to establish rat model. Rats in the sham operation group were treated with injection of identical dose of dimethyl sulfoxide and 0. 9 %o normal saline at identical location which did not contain rotenone. After model establishment, rats in the EA group were treated with EA at "Fengfu" (GV 16) and "Taichong" (LR 3) with continuous wave (2 Hz, 1 mA), which was given 20 min per time, once a day for consecutive 28 days. Rats in the remaining groups were treated with fixation and immobilization without any other intervention. The rats behavioristics changes were observed and scored; immunohisto-chemistry was adopted to test the expression of tyrosine hydroxylase (TH); fluorescence spectrometry was used to detect the activities of 20 S β1, β2, β5; western blot method was applied to measure the expression of 20S proteasome and its a subunit.

RESULTSCompared with the normal group and sham operation group, there was significant change of behavioristics in the model group, and TH positive neuron counting was obviously reduced; after treatment, the behavioristics score in the EA group was lower than that in the model group (P<0. 05), and TH positive neuron counting was significantly increased (P<0. 05). Compared with the normal group and sham operation group, the activities of 20 S β1, β2, β5 in model group were significantly reduced (all P<0. 01), and those in the EA group were higher than those in the model group (P<0. 01). Compared with the normal group and sham operation group, the expression of 20S proteasome and its a subunit was reduced in the model group, and that in the EA group was higher than that in the model group (P<0. 05).

CONCLUSIONEA could improve the loss of dopaminergic neurons induced by rotenone to prevent and treat PD, which is likely to be related with protecting the activity and expression of proteasomes in substantia nigra.