[Electroacupuncture improved locomotor function by regulating expression of tyrosine hydroxylase and α-synuclein proteins and transcription activating factor 6 and transcription factor X box binding protein 1 mRNAs in substantia nigra of rats with Parkinson's disease]

Objective: To observe the effect of electroacupuncture (EA) on behavioral changes, and expression of tyrosine hydroxylase (TH), α-synuclein(α-syn), transcription activating factor 6 (ATF6) and transcription factor X box binding protein 1 (XBP-1) in the substantia nigra of Parkinson's disease (PD) rats, so as to explore its mechanisms underlying improvement of motor function.

Methods: Thirty-six male SD rats were randomly divided into control, model and EA groups (n=12 rats in each group). The PD model was established by subcutaneous injection of rotenone (2 mg/kg) at the neck and back, once a day for 28 days. EA (2 Hz, 1 mA) was applied to "Fengfu" (GV16) and bilateral "Taichong" (LR3) for 20 min, once a day for 14 successive days. The voluntary motor behavioral changes (total distance, average speed, total movement time, total rest time in 8 min) were detected by open field tests. The immuno-activity of TH and α-syn in the substantia nigra was detected by immunohistochemistry, and the expression of ATF6 mRNA and XBP-1 mRNA detected by fluorescence real-time quantitative PCR.

Results: Following modeling and compared with the control group, the total distance, average speed and total movement time of voluntary movement were significantly decreased (P<0.01), and the total rest time was significantly increased (P<0.01). Moreover, the expression of TH was significantly decreased (P<0.01), and that of α-syn protein, ATF6 mRNA and XBP-1 mRNA significantly increased in the model group in comparison with the control group (P<0.01). After the intervention, the total distance, average speed, and total movement time of voluntary movement in the EA group were considerably higher than those in the model group (P<0.01), and the total rest time was obviously decreased in the EA group (P<0.01). The expression level of TH was significantly increased (P<0.01), and those of α-syn, ATF6 mRNA and XBP-1 mRNA were notably decreased in the EA group compared with the model group (P<0.01).

Conclusion: EA intervention can improve the locomotor function in PD model rats, which is associated with its functions in up-regulating the expression of TH protein and down-regulating the expression of α-syn protein, and ATF6 mRNA and XBP-1 mRNA in the substantia nigra of mesencephalon.