褪黑素对溴氰菊酯致大鼠脑组织氧化损伤的保护作用

Protective effect of melatonin on oxidative damage by deltamethrin in rat brain

目的探讨褪黑素（melatonin，MT）对溴氰菊酯（dehamethrin，DM）诱发大鼠大脑皮层、海马、小脑组织氧化性损伤的保护作用。方法35只Wistar雄性大鼠按体重随机分为5组：橄榄油对照组（1ml／kg橄榄油）、MT对照组（25．0mg／kgM1T）、DM组（12．5mg／kgDM）、MTl组（25．0mg／kgMT＋12．5ms／ksDM）、MT2组（2．5mg／kgMT＋12．5ms／kgDM）。每组7只，每组连续5d腹腔注射相应剂量药物。第5天给药后4h，每组大鼠分别断头处死，Spectramx M2多模式全能酶标仪比色测定大鼠大脑皮层、海马、小脑组织匀浆上清中丙二醛（MDA）、谷胱甘肽（GSH）含量和超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、谷胱甘肽过氧化物酶（GSH．Px）活力。结果与橄榄油对照组相比，DM组大脑皮层、海马、小脑组织MDA含量分别上升28．10％、39．25％、56．39％，差异有统计学意义（P〈0．05），大脑皮层、海马组织GSH—Px活力分别下降24．08％、45．01％，小脑组织CAT活力降低27．83％，差异有统计学意义（P〈0．05）。与DM组相比，MTl组大脑皮层、海马、小脑组织的MDA含量分别下降31．12％、41．49％、32．69％，差异有统计学意义（尸如．05）；MT1组大脑皮层的GSH含量、CAT、GSH-Px活力分别升高了48．33％、36．11％、56．59％，MT1组海马组织的GSH含量、CAT、GSH-Px活力分别升高了64．51％、30．32％、79．35％。差异均有统计学意义（P〈0．05）；MT2组大脑皮层、海马MDA含量分别下降了22．96％、25．00％。MT2组海马组织的GSH-Px活力升高了123．33％，差异有统计学意义（P〈0．05）。结论DM能诱发大鼠脑组织的氧化损伤，MT对DM引起的大鼠脑组织的氧化损伤有预防作用。

Objective To study the potential protective effect of melatonin on the oxidative damage induced by deltamethrin in cerebral cortex, hippocampus and cerebellum of rats. Methods 35 male wistar rats were randomly divided into five groups（seven rats per group）： olive oil control, dehamethrin-treated（12.5 mg/kg）, melatonin（25.0 mg/kg） and deltamethrin plus melatonin （25.0 mg/kg, 2.5 mg/kg respectively） group. Levels of malondialdehyde （MDA） and the activity of superoxide dismutase （SOD）, catalase （CAT）, glutathione peroxidase （GSH-Px）, glutathione （GSH） in cerebral cortex, hippocampus and cerebellum were determined after 5 days of DM treatments. Results MDA content in cerebral cortex ,hippocampus and cerebellum tissue of the DM-treated rats were significantly higher than those in control group ,and compared with DM-treated group , MDA content in those tissue of MT ＋ DM-treated group have significantly decreased after 5days of DM exposure （P〈0.05）. Activities of GSH-Px in DM-treated group were significantly lower than those in control group, and those in the MT＋DM group were significantly higher than DM group（P〈0.05）. Conclusion DM can induce the oxidative damage in rat brain and melatonin has protective effects on dehamethrin-induced oxidative damage in hippocampus, cerebral cortex and cerebellum of rats.