Apelin-B对血管性痴呆大鼠学习记忆功能的影响

The effects of apelin-13 on learning and memory function in vascular dementia rats

目的探讨Apelin-13对血管性痴呆(VD)大鼠的学习和记忆功能的影响。方法大鼠腹腔注射亚硝基铁氰化钠,再两次夹闭颈总动脉再通法制备VD动物模型,造模成功大鼠随机分为模型组、Apelin-13 50μg/kg组、Apelin-13 100μg/kg组,假手术组只分离双侧颈总动脉不夹闭。术后侧脑室注射给药,给药组按50μg/kg和100μg/kg给予Apelin-13 5μl,模型组和假手术组分别注射等量蒸馏水。术后24 h取脑,进行2,3,5-三苯基氯化四氮唑(TTC)染色,观察其对大鼠脑组织缺血情况的影响;1 w后跳台实验检测各组大鼠记忆功能;跳台实验后麻醉大鼠取脑进行尼氏染色,观察神经元的受损情况。结果在TTC染色中,与模型组比较,Apelin-13 50μg/kg组大鼠的脑缺血面积明显缩小,Apelin-13 100μg/kg组缺血区基本消失。与模型组比较,Apelin-1350μg/kg组、Apelin-13 100μg/kg组大鼠跳台潜伏期显著延长(P<0. 05,P<0. 01);Apelin-13 100μg/kg组大鼠跳台错误次数比减少(P<0. 05)。尼氏染色后,Apelin-13 50μg/kg组CA1、CA3区神经细胞数量增多,形态趋于完整,核仁分明;Apelin-13 100μg/kg组神经元数明显增多,细胞排列紧密,形态正常,尼氏体多且清晰。结论 Apelin-13能够明显改善VD大鼠的记忆功能,其机制可能与改善脑组织缺血、保护神经元有关。

Objective To study the effects of apelin-13 on learning and memory function in vascular dementia(VD) rats.Methods After the treatment of sodium nitroprusside,the VD animal model was established by repeated ischemia and reperfusion of bilateral common carotid artery. The rats were randomly divided into sham,model,apelin-13 50,100 μg/kg groups. The ischemia of brain was observed by TTC staining,the cognitive memory function was observed by step-down test. The conditions of nerve damage were observed by Nissl staining.Results Compared with those of model group,the cerebral ischemia areas in apelin-13 50,100μg/kg groups were decreased obviously. In the step-down test,compared with that of model group( 55 ± 6. 33),the step-down latency of apelin-13 50 μg/kg group( 160.32±145. 01),apelin-13 100 μg/kg group(204±134.35) was prolonged( P< 0.05,P< 0.01);the error time of apelin-13 100 μg/kg group( 0.6±0. 89) was decreased( P< 0. 05). Compared with that of model group,the neuronal integrity of hippocampus in apelin-13 50,100 μg/kg groups was improved obviously,and the Nissl bodies were abundant and clearly visible.Conclusions Apelin-13 could improve the memory function of VD rats,the mechanism might be related to improving brain ischemia and protecting neurons.