The effect of gastrodin on expression of apoptosis and Tyrosine hydroxylase neurons in substantia nigra pars compacta in rats of Parkinson' s disease

Objective To investigate the etiopathogenesis of Parkinson' s disease (PD) and the mechanism of action of the gastrodin in order to prevent and cure PD. Methods Male Wistar rats were left-striatum injected with 6-OHDA (20 μg) to establish PD model. To observe the effect of gastrodin on the expression of Tyrosine hydroxylase positive (TH +) and Caspase-3 positive (Caspase-3 +) neurons in substantia nigra pars compacta (SNpc) and ventral tegmental area (VTA) by immunohistochemistry technique. Results There were statistically significant differences in the levels of TH + neurons in SNpc and VTA in rats of PD disease between groups (F = 13.29,5.04, P ＜0.01). To compared with normal group[(32.13 ±4.84), (30.23 ± 3.21)], the levels of TH + neurons in SNpc and VTA in rats in model group (18.89 ± 3.73,24.20 ± 6.35) were significantly decreased (P ＜ 0.01),the loss of TH + neurons declined after treatment with gastrodin or madopar, the levels of TH + neurons in SNpc and VTA in rats in small dose group[(26. 24 ± 3.06), (26.31 ± 6. 1)], in middle dose group[(22.4 ± 3.81),(26.91 ±6.28)], in large dose group[(20.95 ±4.71),(27.3 ±7.1)]and in madopar group[(27.89 ±4. 56), (25.97 ±5.14)]were obviously increased, the levels of TH + neurons in SNpc in rats in small dose group and in madopar group were significantly increased (P ＜ 0.05). There were statistically significant differences in the levels of Caspase-3 + neurons in SNpc and VTA of rats of PD disease between groups (F = 6. 09,5. 53, P ＜ 0. 01).To compared with normal group[(9.83 ± 3.03), (7.04 ± 1.76)], the levels of Caspase-3 + neurons in SNpc and VTA in rats in model group[(14.53 ± 2.33), (12.84 ± 2.58)]were significantly increased (P ＜ 0.01), the levels of Caspase-3 .+ neurons in SNpc and VTA in rats in small dose group[(10.68 ± 1.83), (7.72 ± 1.92)], in middle dose group[(11.29 ± 2.8), (10.38 ± 3.79)], in large dose group[(11.89 ± 2.97), (11.37 ± 1.86)]and in madopar group[(9.99 ± 3.3), (10.69 ± 3.11)]were obviously decreased, the levels of Caspase-3 + neurons in SNpc in madopar group and in VTA in small dose group were significantly decreased (P ＜ 0.05). The trend of change of TH + neurons is opposite to that of Caspase-3 + neurons in gastrodin or madopar treatment groups. Conclusion Gastrodin may suppress the loss and apoptosis in SNpc by adjusting Caspase-3. The effect of small dose group is better,suggesting gastrodin can have different neuroprotection on dopamine neuron. Key words: Gastrodin ; 6-hydroxydopamine(6-OHDA) ;  Rats;  Apoptosis; Tyrosine hydroxylase