饱和氢盐水减轻大鼠急性放射性脑损伤早期的氧化应激

Hydrogen-rich saline alleviation on the oxidative stress and early-phase radiation-induced brain injury in rats

目的探讨饱和氢盐水对电离辐射诱发的脑组织损伤的保护作用。方法成年4月龄健康SD大鼠45只，采用随机数字表法分为健康对照组，盐水治疗组和氢水治疗组，再根据照射后时间分为1、3、7和14d4个时间组，每组5只。4MeV电子线对大鼠进行单次垂直全脑照射，吸收剂量率为200cGy／min，吸收剂量20Gy。氢水治疗组大鼠于照射后即刻、照后连续3d给予饱和氢盐水腹腔注射，分别于照射后1、3、7和14d处死大鼠，取脑组织制作匀浆，分光光度计检测超氧化物歧化酶（SOD）、丙二醛（MDA）、8-羟基脱氧鸟嘌呤（8-OHdG）含量。HE染色观察海马区脑组织病理变化。结果7和14d时氢水治疗组脑组织含水量明显小于盐水治疗组（t=3．78、3．18，P〈0．05），SOD水平1—7d时氢水治疗组明显高于盐水治疗组（t=2．41—2．92，P〈0．05），MDA水平明显低于盐水治疗组（t=4．01—6．03，P〈0．05），持续到14d，8-OHdG含量1—7d氢水治疗组明显低于盐水治疗组（t=2．33、2．71、2．33，P〈0．05）。海马区神经细胞损伤明显轻于对照组。结论饱和氢盐水对大鼠急性放射性脑损伤早期有保护作用。

Objective To investigate the effect of hydrogen on radiation-induced acute injury in rat brain. Methods Forty-five mature Sprague-Dawley rats were randomly divided into three groups： saline therapy group, hydrogen therapy group and healthy control group. The whole brain of SD rat was irradiated with single dose of 20 Gy by 4 MeV electrons. Rats in therapy group were injected with hydrogen-rich saline after irradiation and were sacrificed at 1, 3, 7, 14 d post-irradiation. The changes of malonaldehyde （MDA）, superoxidase dismutase （SOD） and 8-hydroxydeoxygunosine （8-OHdG） in brain homogenate and the pathological changes in brain hippocampus were observed. Results The brain water content （ t = 3.78,3.18 ,P 〈 0.05 ） and the contents of 8-OHdG （ t = 2. 33, 2.71, 2. 33 ,P 〈 0.05 ） in the therapy group was lower than the control group at 7 d and 14 d post-irradiation. The contents of SOD were significantly higher（t = 2.41 - 2. 92, P 〈 0. 05 ） from 1 to 7 day, while the contents of MDA were significantly lower in therapy group than those in the control group from 1 to 14 day post-irradiation （ t = 4.01- 6. 20, P 〈 0.05）. Moreover, the damage degree in the nerve cells of hippocampus was less compared to the control group. Conclusions The hydrogen-rich saline could have protection role in irradiation-induced acute brain injury in rats.