CD44基因敲除对小鼠行为能力的影响

Effects of CD44 gene knockout on behavioral abilities in mice

目的 通过动物行为学实验探究CD44基因敲除对小鼠行为能力的影响。方法 将纯合C57BL/6J CD44基因敲除(CD44 knockout, CD44 KO)小鼠与野生型(wild type, WT)小鼠作对比,进行平衡木实验、转棒实验、旷场实验、高架十字实验、悬尾实验、强迫游泳实验、新物体识别实验、三箱社交实验和水迷宫实验,分析比较两组小鼠的行为学差异。结果 在三箱社交实验Stage 3阶段,WT雌性小鼠对新同类的探索时间要多于CD44 KO雌性小鼠(P=0.0475)。水迷宫定位航行实验中第5~7天,CD44 KO组小鼠到达目标区域所需时间长于WT组小鼠(P=0.0147、0.0182、0.0233)。水迷宫空间探索实验中,CD44 KO组小鼠到达目标区域次数更少(P=0.0128),初次到达所需时间更长(P=0.0003)。从初次到达目标区域所需时间方面分析,CD44 KO组内雄性所需时间少于雌性(P=0.049),CD44 KO雄性小鼠所需时间多于WT雄性小鼠(P=0.0137),CD44 KO雌性小鼠所需时间也多于WT雌性小鼠(P=0.0036)。在平衡木实验、转棒实验、旷场实验、高架十字实验、悬尾实验、强迫游泳实验和新物体识别实验结果中,各组未见明显差异。结论 CD44 KO小鼠与WT小鼠相比,学习记忆能力明显下降,以第5~7天最为显著,空间记忆能力也明显减弱。同时,CD44 KO的雌性小鼠的社交趋向性要弱于WT雌性小鼠。在运动协调能力、平衡能力、耐力、焦虑、抑郁等方面,CD44 KO小鼠与WT小鼠未见明显差异。

Objective To explore the effects of CD44 gene knockout on behavioral abilities in mice by animal behavior experiment. Methods Beam balance experiment, rotarod experiment, open field experiment, elevated plus-maze experiment, tail suspension experiment, forced swimming experiment, novel object recognition experiment, three-chamber social experiment and Morris water maze experiment were carried out to analyze and compare the behavioral differences between homozygous C57 BL/6 J CD44 knockout(CD44 KO) mice and wild type(WT) mice. Results In Stage 3 of the three-chamber social experiment, WT female mice were seen to spend more time exploring novel objects than female mice in the CD44 KO group(P=0.0475). From day 5 to day 7 in the water maze navigation experiment, mice in CD44 KO group were observed to take longer to reach the target area than WT mice(P=0.0147, 0.0182, 0.0233). In the water maze space exploration experiment, mice in the CD44 KO group tended to reach the target area fewer times(P=0.0128) and took longer time to reach the target area for the first time(P=0.0003). The time that males in the CD44 KO group took to reach the target area for the first time was less than that taken by females(P=0.049). Additionally, males in the CD44 KO group took more time than WT males(P=0.0137), and females in the CD44 KO group also took more time than WT females(P=0.0036). There were no significant differences in the result of the beam balance experiment, rotarod experiment, open field experiment, elevated plus maze experiment, tail suspension experiment, forced swimming experiment and novel object recognition experiment between the two groups. Conclusions Compared with WT mice, CD44 KO mice were observed to have significantly decreased learning and memory ability, especially in the 5 th~7 th day. In addition, their spatial memory ability was obviously weakened. Meanwhile, CD44 KO female mice were seen to have weaker social propensity than WT female mice. However, no significant differences were noted between CD44 KO mice and WT mice in the aspects of sports coordination ability, balance ability, endurance, anxiety and depression.