No spatial memory deficit exists in Kunming mice that recently recovered from motor defects following 3-nitropropionic acid intoxication

3-硝基丙酸中毒昆明小鼠恢复运动功能后没有空间记忆缺陷(英文)

Objective Numerous studies have described both motor defects and cognitive impairments in several strains of rodents following 3-nitropropionic acid （3-NP） intoxication. In the present study, we investigated spatial recognition memory in Kunming mice that just recovered from motor defects induced by 3-NP. Methods Mouse model was made by systemic subacute 3-NP treatment, and spatial recognition memory was measured through the Y-maze Test, a simple two-trial recognition test. Results （1） On day 15 following 3-NP treatment, affected Kunming mice did not show motor defects in the Rotarod test and presented normal gait again. （2） In the following Y-maze test after lh interval, the percentage （90.0%） of mice showing novel ann preference in 3-NP treatment group was significantly higher than the random chance level （50%）, although it was only slightly higher than that （83.3%） in control group. On day 45 after 3-NP treatment, mice failed to choose unfamiliar novel arm as first choice, and the same occured in the control group. （3） For both post-intoxicated （on day 15 and day 45 following 3-NP treatment） and control groups, the duration in the novel ann and the frequency of entering it, were longer and higher compared with familiar start and other arms. For these mice that recently recovered from motor defects following 3-NP intoxication, no spatial memory deficits were observed through Y-maze Test. Conclusion Kunming mice used in our assays might possess resistance to cognitive impairment induced by 3-NP, which is consistent with previous findings in Swiss EPM-M1 mice.

目的许多研究表明,啮齿类动物品系在3-硝基丙酸(3-NP)中毒后,有运动与认知两方面的损伤。本文旨在研究3-NP中毒的昆明小鼠在运动恢复后的空间认知记忆状况。方法采用亚急性系统给予3-NP的方式制作小鼠实验模型,并通过Y-迷宫,简单双试法来测定空间认知记忆水平。结果(1)3-NP处理后15d,受损昆明小鼠步态正常,在转杆测试中不再显示运动缺陷;(2)间隔1h后进行Y-迷宫测试,经过3-NP处理后15d小鼠对新臂的偏好(90.0%)显著高于随机水平(50.0%),仅稍高于对照组(83.3%),而3-NP处理后45d小鼠及对照组小鼠首选不熟悉的新臂状况与随机水平没有显著差异;(3)不管是中毒后小鼠(分别为3-NP处理后15天及45天)还是对照组小鼠,在新臂的停留时间及反复进入新臂的次数均显著高于熟悉的起始臂和其他臂。在对3-NP中毒后运动恢复了的小鼠进行Y-迷宫测试没有观察到空间记忆障碍。结论结果提示本实验所使用的昆明小鼠可能对于3-NP所致认知缺陷存在耐受性,3-硝基丙酸中毒昆明小鼠恢复运动功能后没有空间记忆缺陷,这与早期在SwissEPM-M小鼠上的发现相一致。