大鼠配对前吗啡成瘾及戒断对子代焦虑样行为和学习记忆的影响

目的 研究大鼠配对前经历吗啡成瘾及戒断对其子代焦虑样行为和学习记忆的影响.方法 8周龄健康Sprague-Dawleyda大鼠24只,雌雄各半. 12只大鼠(雌雄各半)腹腔内注射盐酸吗啡10 d,2次/d,起始剂量为5 mg/kg,逐日递增5 mg,至第10天为50 mg/kg,另12只大鼠用相同方式注射同剂量的生理盐水.戒断后第21天,雌雄大鼠配对分组,1组:成瘾雄鼠+成瘾雌鼠;2组:成瘾雄鼠+生理盐水雌鼠;3组:生理盐水雄鼠+成瘾雌鼠;4组:生理盐水雄鼠+生理盐水雌鼠.每组内雌雄各3只,按上述分组配对合笼.各组所产子代鼠8周时,对其进行高架十字迷宫、旷场行为和水迷宫测试.结果 高架十字迷宫测试,1,2,3组雌雄子代在开放臂停留时间百分比[分别为(2.49±0.91)%,(0.45±0.10)%、(3.34±1.12)%,(5.51±1.60)%、(3.15±0.52)%,(2.09±0.70)%]低于4组雌雄子代(10.41±2.64)%,(9.32±1.63)%,差异具有显著性( P <0.01);旷场行为测试,1,2,3组雌雄子代在中央格停留时间百分比[分别为(3.91±0.82)%,(2.63±0.41)%、(4.31±0.62)%,(2.75±0.72)%、(3.71±0.41)%,(2.04±0.39)%]低于4组雌雄子代(13.97±0.61)%,(7.71±0.21)%,差异具有显著性( P <0.01).水迷宫测试,每组子代找到平台的平均潜伏期、在目标象限的时间均差异无显著性( P >0.05).结论 亲代经历吗啡成瘾及戒断后会导致子代产生焦虑样行为,但对学习记忆无明显影响.

Effect of morphine addiction and withdrawal in parents prior to mating on the anxiety-like behavior and spatial learning-memory in adult offspring rats

Objective To study the impact of morphine addiction and withdrawal in parents prior to mating to the anxiety-like behaviour and spatial learning-memory in adult offspring rats. Methods 24 rats(12 female and 12 male) were used.6 males and 6 females were intraperitoneally injected with morphine twice a day for 10 days in ascending dosage schedule,accordingly. The rest of rats were injected with saline of the same volume. Twenty one days after morphine withdrawal,rats were mated. Then each one male with one female were housed(coupled) per cage as four groups for coupling:addicted males + addicted females(Group 1);addicted males + saline females(Group 2);saline males + addicted females(Group 3);saline males+ saline females(Group 4).When the offspring was 8 weeks of age,the anxiety-like behavior and spatial learning-memory were assessed in the elevated-plus maze test, the open-field test and morris water maze respectively.Results Compared with the female and male's offspring in group 4[(10.41±2.64,9.32±1.63)％],the female and male's offspring in group 1,2,3 exhibited the percent of time spent in open arms[(2.49±0.91, 0.45±0.10)％,(3.34±1.12,5.51±1.60)％,(3.15±0.52,2.09±0.70)％] were reduced obviously in the elevated plus maze( P <0.01). Similarly, Compared with the female and male's offspring in group 4[(13.97±0.61,7.71±0.21)％], the female and male's offspring in group 1,2,3 exhibited the percent of time spent in the center zone [(3.91±0.82,2.63±0.41)％,(4.31±0.62,2.75±0.72)％,(3.71±0.41,2.04±0.39)％]were reduced significantly in the open field test( P <0.001).But the offspring in group 1,2,3,4 exhibited the escape latency and the percent of time spent in the target quadrant were no difference in the morris water maze( P >0.05). Conclusion These findings suggest that parents experiencing morphine addiction and withdrawal prior to mating can result in the offsprings anxiety-like behavior,but have no obvious effect on spatial-memory learning.