[Effects of penetration therapy with scalp electroacupuncture on gene expressions of nerve growth factors in substantia nigra of rats with Parkinson's disease].

Objective: To explore the protective mechanism of penetration therapy with scalp electroacupuncture on Parkinson's disease (PD).

Methods: Thirty-six Wistar rats were randomly divided into a normal group, a sham operation group, a model group and a penetration therapy group, 9 rats in each group. The sham operation group was operated by micro-injection with normal saline in the left corpus striatum. The model group and penetration therapy group were generated by micro-injection with 6-hydroxydopamine in the left corpus striatum to prepare rotation model of PD. The penetration therapy group was treated by penetration therapy with scalp electroacupuncture through "Baihui" (GV 20) to "Taiyang" (EX-HN 5), once each day, 6 days for one course, altogether 2 courses, and there was no treatment in the other two groups. (1) Immunohistochemical method was used to test the morphology and count of positive cells of tyrosine hydroxylase (TH). (2) In situ hybridization histochemistry was applied to detect the mRNA expression of brain-derived neurotrophic factor (BDNF).

Results: (1) The areal density (AD), numerical density (ND) and integrating optic density (IOD) of the positive neurons of TH in substantia nigra in the penetration therapy group were 0.065 +/- 0.011, 0.014 +/- 0.003 and 0.470 +/- 0.099, respectively, which were higher than 0.039 +/- 0.008, 0.008 +/- 0.002 and 0.266 +/- 0.065 in the model group (all P < 0.05). (2) The AD, ND and IOD of the mRNA expression of BDNF in substantia nigra in the penetration therapy group were 0.100 +/- 0.012, 0.014 +/- 0.003 and 1.158 +/- 0.130, respectively, which were higher than 0.047 +/- 0.012, 0.007 +/- 0.001 and 0.602 +/- 0.108 in the model group (all P < 0.05).

Conclusion: The penetration therapy with scalp electroacupuncture has a better protective effect on dopaminergic neurons in substantia nigra of rats with PD. The protective mechanism is related to the provocation of neural nourishment so as to improve the morphous of dopaminergic neurons and increase the number of dopaminergic neurons.