慢性束缚应激对SD和Wistar大鼠学习记忆能力的影响

目的探讨慢性束缚应激对Wistar、SD两种品系大鼠学习记忆能力的影响,为应激模型中实验动物的选择提供依据。方法对两种品系大鼠(Wistar、SD)采用每天束缚10 h,束缚28 d建立慢性应激模型。采用物体认知新物体识别实验和Morris水迷宫空间学习、工作记忆行为学检测方法,观察束缚应激对两种品系实验动物学习记忆能力的影响。结果束缚28 d后,物体识别实验中,Wistar、SD模型组的辨别指数(discrimination index,DI)均低于对照组,但只有SD两组间差异存在显著性(P0.05);水迷宫空间学习阶段,SD模型组潜伏期高于对照组,第5天差异有显著性(P0.05),而Wistar模型组与对照组间的潜伏期没有差异;水迷宫工作记忆阶段,SD大鼠模型组与正常组比较,潜伏期显著增加(P0.05),Wistar模型大鼠的潜伏期与对照组比较没有显著差异。结论新物体识别实验和水迷宫实验,这两种反应动物不同学习记忆能力的行为学实验结果都表明,慢性束缚应激(10 h,28 d)对SD大鼠学习记忆能力的损伤较Wistar大鼠明显。SD大鼠可能更适合作为慢性应激所致学习记忆损伤动物模型。

Effects of chronic restraint stress on learning and memory in SD and Wistar rats

Objective To investigate the effects of chronic restraint stress on learning and memory in Wistar and Sprague-Dawley （SD） rats.Methods Healthy adult male Wistar rats （n=6） and Sprague-Dawley rats （n=6） were subjected to restraint stress 10 h daily for 28 days.After that, all rats were tested for recognition memory by novel object recognition test , and spatial memory and working memory by Morris water maze test .Results After restraint for 10 h daily for 28 days, the restraint rats of the two strains demonstrated lower discrimination index （DI）than the control group, but on-ly SD rats showed significant difference （ P〈0.05 ） .The restraint SD rats showed higher escape latency than the control rats, and on the 5th day the difference became significant （P〈0.05）, and there was no significant difference between Wistar restraint and control rats .The working memory test showed that restraint SD rats exibited longer escape latency than＆amp;nbsp;the control rats （P〈0.05）, while Wistar rats didn’t show significant difference between the two groups .Conclusions The results of this study demonstrate that the impairments of learning and memory in SD rats subjected to restraint 10 hour per day for 28 days are more serious than that in the Wistar rats .Therefore , SD rats may be a better choice as an animal model to study the effects of chronic restraint stress on learning and memory impairment .