Department of Psychiatry, University of Florida, Gainesville, FL, USA.
Department of Psychiatry, University of Florida, Gainesville, FL, USA; Department of Neuroscience, University of Florida, Gainesville, FL, USA; Center for Addiction Research and Education, University of Florida, Gainesville, FL, USA.
Pharmacol Biochem Behav. 2021 May;204:173168. doi: 10.1016/j.pbb.2021.173168. Epub 2021 Mar 5.
There is a growing need for a better understanding of sex differences in animal models of psychiatric disorders. The elevated plus-maze (EPM) test and large open field (LOF) test are widely used to study anxiety-like behavior in rodents. Our studies explored sex differences in anxiety and activity parameters in the LOF and EPM and determined whether these parameters correlate within and between tests. Drug naïve adult male and female Wistar rats (n = 47/sex) were used for the studies, and the rats were tested for 5 min in the EPM and 10 min in the LOF. The females spent more time on the open arms of the EPM and made more open arms entries than the males. The females also spent more time in the center zone of the LOF and made more center zone entries. The females traveled a greater distance in the LOF and EPM. There was a moderate positive correlation between time on the open arms of the EPM and time in the center zone of the LOF. There was also a moderate positive correlation between open arms entries in the EPM and center zone entries in the LOF. A hierarchical cluster analysis revealed one cluster with LOF parameters, one cluster with EPM parameters, and one cluster with parameters related to the avoidance of open spaces. In conclusion, these findings indicate that female rats display less anxiety-like behavior in the EPM and LOF. Furthermore, there are sex differences for almost all behavioral parameters in these anxiety tests.
越来越需要更好地理解精神疾病动物模型中的性别差异。高架十字迷宫（EPM）测试和大旷场（LOF）测试广泛用于研究啮齿动物的类焦虑行为。我们的研究探讨了 LOF 和 EPM 中焦虑和活动参数的性别差异，并确定这些参数在测试内和测试间是否相关。使用未经药物处理的成年雄性和雌性 Wistar 大鼠（n=47/性别）进行研究，大鼠在 EPM 中测试 5 分钟，在 LOF 中测试 10 分钟。雌性在 EPM 的开放臂上花费的时间更多，进入开放臂的次数也比雄性多。雌性在 LOF 的中央区域花费的时间也更多，进入中央区域的次数也更多。雌性在 LOF 和 EPM 中行进的距离更大。EPM 的开放臂时间和 LOF 的中央区域时间之间存在中度正相关。EPM 的开放臂进入次数和 LOF 的中央区域进入次数之间也存在中度正相关。层次聚类分析显示，一个聚类与 LOF 参数相关，一个聚类与 EPM 参数相关，一个聚类与回避开放空间的参数相关。总之，这些发现表明雌性大鼠在 EPM 和 LOF 中表现出较少的类焦虑行为。此外，这些焦虑测试中的几乎所有行为参数都存在性别差异。
