Abstract: Objective To observe the effects of chronic unpredictable mild stress ( CUMS) combined with solitary rearing on the behavior, serum 5-HT and neurons in the hippocampus of spontaneously hypertensive rats ( SHR) . Method Twenty SHR rats were randomly divided into SHR group and model group, and the same number of Sprague-Dawley ( SD) rats were set as the control group. Predictive stress (CUMS) combined with solitary rearing was used to intervene for 5 weeks, and the rest of the groups were fed normally. The caudal arterial blood pressure of rats in each group was measured on the 14th day and at the end of modeling, respectively. Open-field experiment and sugar water consumption experiment were performed. Forced swimming experiment was conducted after modeling, 5-HT content in serum was detected by ELISA, and activity and arrangement of hippocampal neurons and the number of neurons’ Nissl bodies were observed by HE staining and Nissl staining. Result Compared with the control group, the blood pressure of SHR group increased significantly ( P < 0. 01) , body weight growth rate increased obviously(P<0. 01) , the level of activity and the number of upright, sugar water consumption rate and forced swimming fixed time, 5-HT content there was no significant difference (P>0. 05) , roundness, hippocampal neurons form order, nissl bodies and more dense; Systolic blood pressure of model group was significantly increased (P< 0. 01) , body weight growth rate was not significantly different ( P > 0. 05) , horizontal activity and upright times, sugar water consumption rate were significantly decreased (P<0. 05, P<0. 01) , forced swimming immobile time was significantly increased (P<0. 01) , 5-HT content was significantly decreased (P<0. 01) . The arrangement of hippocampal neurons was loose and the nite body was apoptotic. Compared with SHR group, systolic blood pressure in model group was not significantly increased (P>0. 05) , body weight growth rate, horizontal activity and upright times, sugar water consumption rate were significantly decreased ( P<0. 01) , the immobile time of forced swimming was significantly increased ( P < 0. 01 ) , 5-HT content was significantly decreased ( P < 0. 01 ) , the arrangement of hippocampal neurons was loose, and Nissl bodies apoptosis. Conclusion Chronic unpredictable stress (CUMS) combined with solitary rearing induced depression-like changes in behavior, neurotransmitters and hippocampal neurons in SHR rats.

Key words: hypertension complicated with depression, chronic unpredictable mild stress, solitary rearing, SHR, model

摘要： 目的 观察慢性不可预知温和应激(CUMS)联合孤养对自发性高血压大鼠( SHR) 行为学、血清中 5-HT 与海马区神经元的影响。 方法 SHR 大鼠 20 只,随机均分为高血压对照组和模型组,另设同数 Sprague-Dawley( SD) 大鼠为空白组。 模型组以 CUMS 联合孤养的方法干预 5 周,其余组正常饲养。 分别在造模 14 d 及造模 35 d 后测量各组大鼠尾动脉血压,进行旷场实验,糖水消耗实验;造模结束后进行强迫游泳实验,ELISA 法检测血清中 5-HT 含量,HE 和尼氏染色观察海马神经元的活性、排列情况以及神经元尼氏小体的数量。 结果 与空白组比较,高血压对照组大鼠收缩压明显升高(P<0. 01) ,体质量增长率明显增大( P<0. 01) ,水平活动与直立次数、糖水消耗率及不动时间、血清中 5-HT 含量无统计学差异(P>0. 05) ,海马神经元细胞形态圆整,排列整齐,尼氏小体多且密集;模型组大鼠收缩压明显升高(P<0. 01) ,体质量增长率无统计学差异( P>0. 05) ,站立与水平活动次数、糖水消耗率明显降低(P<0. 05,P<0. 01) ,不动时间明显增加(P< 0. 01) ,血清中 5-HT 含量明显降低( P< 0. 01) ,海马神经元排列疏松,尼氏体凋亡。 与高血压对照组比较,模型组大鼠收缩压无明显升高( P> 0. 05) ,体质量增长率、站立与水平活动次数、糖水消耗率明显降低(P<0. 01) ,不动时间明显增加(P<0. 01) ,血清中 5-HT 含量明显降低(P<0. 01) ,海马神经元排列疏松,尼氏小体凋亡。 结论 采用慢性不可预知温和应激( CUMS) 联合孤养诱导 SHR 大鼠行为学、血清中 5-HT 与海马区神经元呈现抑郁样改变。

关键词: 高血压并发抑郁, 慢性不可预知温和应激, 孤养, 自发性高血压大鼠, 模型