刚地弓形虫RH株感染对BALB／c小鼠情绪行为的影响

目的研究刚地弓形虫RH株感染对BALB／c小鼠学习记忆行为的影响及可能机制。方法将72只周龄、大小相近的雄性BALB／c小鼠采用随机数字表分为生理盐水对照组与不同数量（3×10^3／ml、3×10^4／ml、3×10^5／m1）弓形虫RH株感染组，每组18只。于感染第5周从每组各随机抽取6只分别进行高架十字迷宫实验、旷场实验及强迫游泳实验，观察各组小鼠在实验中情绪行为变化。并记录各项指标进行统计分析。结果在高架迷宫试验与旷场实验中，3×10^3／ml弓形虫感染组小鼠与生理盐水对照组小鼠比较，各项行为学指标无明显差异。在3×10^4／ml、3×10^5／ml弓形虫感染组小鼠与对照组小鼠比较出现明显降低（P〈0．05）．以3×10^5／ml感染组最为明显，其小鼠运动活力（0E＋cE）、进入开放臂次数比例（OE％）、开放臂停留时间比例（OT％）小鼠爬行总格数、中央格在总格数中比例分别为11．08±2．12、28．73±0．59％、25．62±2．33％、32．30±17．26、2．42±0．65％。在强迫游泳试验中，各弓形虫感染组小鼠游泳的静止时间均高于对照组小鼠（P〈0．05），3×10^5／ml感染组静止时间最长，达226．6±1．9S。结论刚地弓形虫RH株感染可引起小鼠情绪行为改变，具有焦虑抑郁倾向。

Effect of Toxoplasma Gondii RH Strain Infection on Emotional Behaviour of BALB/c Mouse

Objective To investigate tbe effects of Toxoplasma gondii RH Strain infection on emotional behaviors of BALB/c mouse. Methods 72 male BALB/c with similar weight and age were randomly divided into 4 groups averagely ： one normal saline control group and other 3 different concentrations of Toxoplasma gondii RH Strain infected groups（ the concentration of tachyzoites was 3 × 10^3/ml,3 × 10^4/ml,3 × 10^5/ ml respectively）. At the 5 th week, elevated plus maze test, open field test and force swimming test were performed to observe the changes of emotional behavior of mice in each group. Results There were no significant effects in elevated plus maze test and open field test between 3 × 10^3/ml Toxoplasma gondii RH Strain infected group and saline control group,However,3 × 10^4/ ml,3 × 10^5/ ml Toxoplasma gondii RH Strain infected groups bare significant effects comparing with their correspondent control groups（P 〈 0. 05 ）. The results of 3 × 10^5/ml Toxoplasma gondii RH Strain infected group about OE ＋ CE, OE%, OT%. The number of crossing, Rate of center crossing were 11.08 ± 2. 12, 28.73 ±0. 59% ,25.62±2.33% ,32.30 ± 17.26,2.42 ±0.65% respectively. In force swimming test,the resting time of every Toxoplasma gondii RH Strain infected group was longer than the control group（P 〈 0. 05）. The resting time of 3 × 10^5/ml Toxoplasma gondii RH Strain infected group could be 226.6 ± 1.9 seconds especially. Conclusion Toxoplasma gondii RH Strain infection can made mouse anxiety and depression.