高压氧对帕金森病大鼠多巴胺神经元保护作用的研究

Neuroprotective effect of hyperbaric oxygenation on dopaminergic neuron in hemiparkinsonian rats

目的探讨高压氧对帕金森病大鼠多巴胺神经元的保护作用。方法将68只雌性SpragueDawley大鼠随机分成5组:注射生理盐水高压氧处理组(A组,n=7)、全程高压氧处理模型组(B组,n=18)、未经高压氧处理模型组(C组,n=7)、造模后高压氧处理组(D组,n=18)、造模前高压氧处理组(E组,n=18)。在实验第1天至第7天给予A组、B组和E组大鼠高压氧治疗;而在实验第8天时,分别向B组、C组、D组及E组大鼠单侧脑黑质内定位注射6羟基多巴胺以制作偏侧帕金森病大鼠模型,给予A组等量生理盐水定位注射。从实验第8天至结束,分别给予A组、B组及D组大鼠高压氧处理;并于造模后第9天,16天及21天每组各处死6只大鼠,取其纹状体用分光光度计测定超氧化物歧化酶(SOD)、丙二醛(MDA)和谷胱甘肽过氧化物酶(GSHPx)含量,选用免疫组织化学方法测定黑质区域内酪氨酸羟化酶(TH)阳性细胞数量及胶质纤维酸性蛋白(GFAP)的表达。结果与C组比较,B、D、E组大鼠病变侧纹状体内SOD及GSHPx活性显著增高,MDA含量及GFAP表达明显降低,6羟基多巴胺毁损黑质区残存的TH阳性细胞数目明显增加。结论高压氧治疗可以显著提高机体抗自由基损伤功能、减弱胶质细胞效应发挥,从而有效保护脑黑质区多巴胺(DA)能神经元功能。

Objective To evaluate the neuroprotective effect of hyperbaric oxygenation（HBO） on dopaminergic neuron in hemiparkinsonian rats. Methods Sixty-eight female Sprague-Dawley rats were randomly divided into five groups： group A,normal rats injecting physiological saline solution into substantia nigra followed by HBO intervention （ n = 7 ） ; group B, Parkinson disease （PD） models with HBO before and after the injection of 6-hydroxydopamine（n = 18; group C, PD models without HBO all through the course（ n = 7）; group D, PD models that with HBO only after the injection of 6-hydroxydopamine（ n = 18） ; group E, PD models with HBO only before the injection of 6-hydroxydopamine（n = 18）. From the 1st to the 7th day, groups A, B and E were under the HBO treatment. On the 8th day, groups B, C, D and group E accepted 6-OHDA solution injections into the right striatum. Group A was given equal physiological saline solution injection of the same dose. From the 9th day onwards, groups A, B and D began to be treated with HBO. On the 9th day, 16th day and 21st day after the models were established, 6 animals of each group were sacrificed, respectively. The levels of Cu/Zn superoxide dismutase （Cu/Zn-SOD）, manganese superoxide dismutase （ MnSOD）, glutathione peroxidase （GSH-Px） and malondialdehyde （MDA） of the striatum were measured by using immunohistochemistry, the expression of glial fibrillary acidic protein （GFAP） and tyrosine hydroxylase（TH）-positive neurons in the right substantia nigra were observed. Results In the groups accepted prevention or treatment of HBO, the numbers of TH-positive neurons and the levels of Cu/Zn-SOD, MnSOD and GSH-Px were significantly increased when compared with group C （ P 〈 0.01, respectively）, and in groups B, D and E, the expression of GFAP and the level of MDA decreased dramatically when compared with group C （ P 〈 0.01, respectively）. Conclusion HBO can attenuate the degree of oxidative stress in the striatum and protect dopaminergic neurons against the toxicity of 6-OHDA in substantia nigra.