Kulesskaya Natalia, Voikar Vootele
Neuroscience Center and Department of Biosciences, P.O. Box 56 (Viikinkaari 4), FIN-00014, University of Helsinki, Finland.
Neuroscience Center and Department of Biosciences, P.O. Box 56 (Viikinkaari 4), FIN-00014, University of Helsinki, Finland.
Physiol Behav. 2014 Jun 22;133:30-8. doi: 10.1016/j.physbeh.2014.05.006. Epub 2014 May 14.
Light-dark box and open field are conventional tests for assessment of anxiety-like behavior in the laboratory mice, based on approach-avoidance conflict. However, except the basic principles, variations in the equipment and procedures are very common. Therefore, contribution of certain methodological issues in different settings was investigated. Three inbred strains (C57BL/6, 129/Sv, DBA/2) and one outbred stock (ICR) of mice were used in the experiments. An effect of initial placement of mice either in the light or dark compartment was studied in the light-dark test. Moreover, two tracking systems were applied - position of the animals was detected either by infrared sensors in square box (1/2 dark) or by videotracking in rectangular box (1/3 dark). Both approaches revealed robust and consistent strain differences in the exploratory behavior. In general, C57BL/6 and ICR mice showed reduced anxiety-like behavior as compared to 129/Sv and DBA/2 strains. However, the latter two strains differed markedly in their behavior. DBA/2 mice displayed high avoidance of the light compartment accompanied by thigmotaxis, whereas the hypoactive 129 mice spent a significant proportion of time in risk-assessment behavior at the opening between two compartments. Starting from the light side increased the time spent in the light compartment and reduced the latency to the first transition. In the open field arena, black floor promoted exploratory behavior - increased time and distance in the center and increased rearing compared to white floor. In conclusion, modifications of the apparatus and procedure had significant effects on approach-avoidance behavior in general whereas the strain rankings remained unaffected.
明暗箱和旷场试验是基于趋避冲突来评估实验室小鼠焦虑样行为的传统测试。然而，除了基本原则外，设备和程序的变化非常普遍。因此，研究了不同环境中某些方法学问题的影响。实验使用了三种近交系小鼠（C57BL/6、129/Sv、DBA/2）和一种远交群小鼠（ICR）。在明暗试验中研究了小鼠最初放置在明或暗隔间的影响。此外，应用了两种跟踪系统——动物的位置通过方盒（1/2暗）中的红外传感器或通过矩形盒（1/3暗）中的视频跟踪来检测。两种方法都揭示了探索行为中强大且一致的品系差异。一般来说，与129/Sv和DBA/2品系相比，C57BL/6和ICR小鼠表现出减少的焦虑样行为。然而，后两个品系的行为有显著差异。DBA/2小鼠表现出对明隔间的高度回避并伴有趋触性，而活动低下的129小鼠在两个隔间之间的开口处花费大量时间进行风险评估行为。从明侧开始增加了在明隔间花费的时间并减少了首次转换的潜伏期。在旷场实验中，与白色地板相比，黑色地板促进了探索行为——在中心区域的时间和距离增加以及直立次数增加。总之，仪器和程序的修改总体上对趋避行为有显著影响，而品系排名不受影响。
