摘要
目的探讨在慢性不可预知性应激(chronic unpredictable stress,CUS)后压力耐受大鼠大脑白质体积及白质内有髓神经纤维总体积的改变,分析对压力的耐受能力是否与大脑白质的改变有关。方法选用50只4~5周龄雄性Sprague-Dawley(SD)大鼠,采用完全随机法分为空白对照组和模型组。模型组的大鼠在给予4周的CUS之后,根据糖水偏好实验(sucrose preference test,SPT)的结果筛选出压力易感组和压力耐受组。采用旷场实验(open field test,OFT)评估各组的行为学水平,运用体视学方法计算各组大鼠白质体积和白质内有髓神经纤维的体积。结果压力易感组的蔗糖偏好百分比显著低于空白对照组和压力耐受组(P<0.01)。压力耐受组OFT总成绩显著优于空白对照组和压力易感组(P<0.01)。压力耐受组的白质体积显著性高于压力易感组(P<0.01),但与空白对照组比较,差异没有统计学意义(P>0.05)。压力耐受组白质的有髓神经纤维总体积显著性高于压力易感组(P<0.01),与空白对照组相比差异没有统计学意义(P>0.05)。结论白质和白质内有髓神经纤维的改变可能与抑郁易感性差异存在关系。
Objective To investigate the changes in the total volume of the white matter and the myelinated nerve fibers in the white matter of stress-resilient rats after chronic unpredictable stress （CUS） and explore whether resilience to stress is related to white matter changes. Methods Fifty 4- to 5-week-old male Sprague-Dawley rats were randomized into the control group and CUS group. The rats in CUS group were exposed to a 4-week CUS, and the stress-susceptible and stress-resilient rats were screened using sucrose preference test. The behavioral changes of the rats were assessed using open field test. In each rat, the white matter volume and the total volume of the myelinated nerve fibers in the white matter were investigated using stereological methods. Results The stress-susceptible rats showed significantly lowered sucrose preference compared with the control rats and stress-resilient rats （P 〈 0.01 ）. The stress-resilient rats had significantly higher total scores in open field test than the control and stress-susceptible rats （P 〈 0.01 ）. The white matter volume of the stress-resilient rats was significantly greater than that of the stress-susceptible rats （ P 〈 0. 01 ） and was similar to that in the control rats （P 〉 0. 05 ）. The total volume of the myelinated nerve fibers in the white matter of the stress-resilient rats was higher than that of the stress-susceptible rats （ P 〈 0.01 ） but similar to that of the control rats （P 〉 0. 05）. Conclusion The changes in the white matter and the myelinated nerve fibers in the white matter might be associated with the differences in the susceptibility to depression.
出处
《第三军医大学学报》
CAS
CSCD
北大核心
2018年第4期316-321,共6页
Journal of Third Military Medical University
基金
国家自然科学基金面上项目(81671259
81501156
81501101)~~
关键词
慢性不可预知性应激
压力耐受
白质
有髓神经纤维
体视学
chronic unpredictable stress
stress resilience
white matter
myelinated nerve fibers
stereology
