对氨基水杨酸钠对染锰大鼠学习记忆及海马GFAP阳性细胞表达的影响

Effects of Sodium P-amino-salicylic Acid on Learning Memory and Expression of GFAP Positive Cells in Hippocampus of Manganese Exposed Rats

目的探讨对氨基水杨酸钠(PAS-Na)对亚急性染锰大鼠学习记忆及海马胶质原纤维酸性蛋白(GFAP)阳性细胞表达的影响。方法雄性SD大鼠40只随机分为正常对照组(对照组)(染锰组)低和高剂量PAS-Na治疗组(L-、H-PAS组)。染锰和PAS治疗大鼠每天腹腔注射(ip)MnCl2·4H2O 15 mg/kg,对照组大鼠ip等容量生理盐水,每周5 d,共3周。接着,PAS治疗大鼠每天背部皮下注射(sc)PAS-Na100或200 mg/kg,其余大鼠背部sc等容量生理盐水,连续5周。用Morris水迷宫检测大鼠学习记忆能力,免疫组织化学方法检测海马CA1区和齿状回GFAP阳性细胞数。结果染锰末周大鼠体重增加明显减低,PAS-Na治疗使染锰大鼠体重明显增加,以高剂量PAS-Na治疗组作用较为明显,差异有统计学意义(P<0.05或P<0.01)。染锰组逃避潜伏期、游泳总路程均比对照组长,H-PAS组逃避潜伏期、游泳总路程比染锰组缩短,差异有统计学意义(P<0.05)。染锰组GFAP阳性细胞数比对照组多,H-PAS组GFAP阳性细胞数较染锰组减少,差异有统计学意义(P<0.05或P<0.01)。结论 PAS-Na对锰致大鼠生长发育迟缓、学习记忆障碍和海马胶质细胞异常增生可能有干预作用。

Objective To explore the effects of sodium p-amino-salicylic acid（PAS-Na） on learning memory and expression of glial fibrillary acidic protein（GFAP） positive cells in hippocampus of sub-acute manganese（Mn） exposed rats.Methods 40 male Sprague-Dawley rats were randomly divided into the control group,Mn exposed group,low and high doses PAS groups.The rats were injected intraperitoneally daily（i.p.） with manganese chloride（MnCl2·4H2O 15 mg/kg）,5 days/week for 3 weeks,followed by a daily subcutaneous injection of low and high doses PAS-Na（100 and 200 mg/kg） as the L-PAS and H-PAS groups respectively at the back for another 5 weeks.The ability of learning memory was tested by Morris Water Maze（MWM） and the GFAP-positive cells in the hippocampal CA1 area and dentate gyrus were detected by immunohistochemical technique.Results The weight gain of Mn exposed group was evidently reduced in the 3rd week and lasted 5 weeks after suspending Mn exposure（P0.05～0.01）.However,a marked weight gain in PAS-Na treatment groups were observed,especially in high dose PAS group（P0.05～0.01）.The escape latency and the total swimming distance of Mn exposed group were longer than those of the control group（P0.05）.The escape latency and swimming distance of the high dose PAS group were obviously shorter than those of the Mn exposed group（P0.05）.GFAP positive cells in the Mn exposed group increased compared with that of the control group（P0.01）.A significant decline of GFAP positive cells was found in the high dose PAS-Na group（P0.05）.Conclusions PAS-Na may have the intervention effect on growth retardation,learing and memory impairment,glial abnormal proliferation in hippocampus of rats induced by manganese.