苯并[a]芘对小鼠的神经毒性及脑组织热应激蛋白水平的影响

Study on the neurotoxicity and brain tissue HSPs level in benzo[a]pyrene exposed mice

目的 研究苯并 [a]芘 (BaP)对小鼠的神经毒性及对脑组织热应激蛋白HSP70、HSP90 β表达的影响。 方法 将 5 0只昆明种小鼠随机分为 5组 ,每组 10只 ,染毒组分为高、中、低 3个剂量 ,并设溶剂对照及空白对照组。染毒组用BaP的植物油溶剂进行腹腔注射处理 ,高、中、低剂量组每次分别注射 7 8、3 2和 1.3mg kgBW ,每周 4次。溶剂对照组用植物油溶剂作平行处理 ,空白对照组不做处理。实验中观察一般情况及神经系统表现 ,实验 8周后取各组小鼠全脑组织 ,观察、称量并计算脑组织脏器系数 ,Westernblot法检测HSP70、HSP90 β水平。结果 ①中、高剂量BaP染毒组小鼠脑组织重明显低于对照组 ,高剂量BaP染毒组小鼠脑组织脏器系数明显低于其他组。②HSP70表达改变以低剂量BaP染毒组相对表达值明显增高为特征 ;HSP90 β表达改变为中、高剂量BaP染毒组相对表达值升高。结论 BaP具有一定的神经毒性。随着染毒剂量增加 ,HSP90 β表达水平增高。

Objective To study the neurotoxicity and brain tissue HSP70,HSP90β level in benzo[a]pyrene exposed mice. Methods 50 Kunming mice were divided into 5 groups randomly,the exposed groups(3 dose level groups), the vehicle control group and the standard control group, every group get 10 mice. The exposed groups were administrated by intraperitoneal injection with BaP dissolved in vegetable oil at 7.8,3.2 and 1.3mg/kgBW once, 4 times/week specially, the vehicle control group was given vegetable oil parallel and the standard control group was not given additional treatment. Observing general conditions and nerve symptoms of the animals. After 8 weeks experiments, the mice were killed and the brains were removed. Detect the ratio of brain-weight /body-weight and the Hsp70 and Hsp90βlevel of the mice brain homogenate by the method of western blot. Results ① In the high and medium dose groups, the brain-weight was lower than that of control groups. In the high dose group, the ratio of brain-weight /body-weight was lower than that of other groups. ② In the low dose BaP group, HSP70 level were much higher than that of control groups. In the medium dose BaP group and high dose BaP group, HSP90β level were higher than that of control groups. Conclusion BaP can damage the never system of the mice; the high the dose was, the high the HSPs90 level were.