雌激素改善小鼠学习记忆的实验研究

目的 :研究雌激素去除 (OVX)与雌激素替代 (ERT)对小鼠T迷宫学习记忆的影响。方法 :3mo鼠龄的雄性C 5 7BL/ 6J小鼠 6 0只 ,随机分 2组 ,分别为假手术组和卵巢切除组 ,每组又分为不给雌激素、给雌激素 7d、给雌激素 4 0d的 3个亚组 ,每组 10只。小鼠摘除卵巢后饲养至 7mo鼠龄进行迷宫实验 ,将 2组小鼠于迷宫测试前 7d和 4 0d分别埋植控释雌激素 (17β 雌二醇 )药丸每丸 0 .18mg ,测试各组小鼠对T迷宫的正确选择次数。结果 :卵巢切除组不给雌激素亚组其正确选择次数明显下降 ,与假手术组的不给雌激素亚组比较 ,d 1,d2和d 3为 (42± 10 ) %vs (5 4± 9) % ,(47± 11) %vs (6 2± 10 ) %和 (5 0± 10 ) %vs (6 8± 10 ) %均P<0 .0 1;给雌激素 7d和 4 0d亚组其正确选择次数明显提高d 1,d 2和d 3为 (5 7± 7) %vs (42±10 ) % ,(6 5± 11) %vs (47± 11) %和 (77± 11) %vs(5 0± 10 ) % (P <0 .0 1) ,而且长期给雌激素亚组其正确选择次数明显高于短期给雌激素亚组。假手术组的不给雌激素和给雌激素组其正确次数差异无显著意义 (P >0 .0 5 )。结论 :雌激素去除明显损害了小鼠的学习记忆能力 ,而雌激素替代可以改善小鼠的学习记忆能力 ,正常小鼠予雌激素负荷并不能影响其学习记忆过程

Experimental study of estrogen in improving learning and memory on mice

AIM: To investigate the effects of ovariectomy and estrogen replacement on learning and memory in mice in T-maze test. METHODS: Sixty female C 57 BL/6 J mice in three months old were randomly divided into sham and ovariectomized (OVX) groups. Each group had estrogen non-treated (Enon). Seven days treated (E 7 d) and forty days treated (E 40 d) subgroups. Each subgroup had ten mice. Mice were ovariectomized and raised until seven months old. 17 β-estradiol time release pellet (0.18 mg/pellet) was given i.c. seven days and forty days before T-maze were tested and then tested the numbers of correct choice in T-maze by mice. RESULTS: The correct choice in Enon subgroup, OVX group, significantly decreased d 1 was (42±10)% vs (54±9)%, d 2 was (47±11)% vs (62±10)%,and d 3 was (50±10)% vs (68±10)%. (P< 0.01, comparied to Enon subgroup in sham group). The correct choice in E 7 d and E 40 d subgroup, OVX group, significantly increased d 1 was (57±7)% vs (42±10)%, d 2 was (65±11)% vs (47±11)% and d 3 was (77±11)% vs (50±10)%. (P<0.01, comparied to Enon subgroup in OVX group). The effects of long-term administration of estrogen (E 40 d) in improving correct choice were better than short-term (E 7 d). There were no differences of correct choice between estrogen treated and non-treated subgroups in sham group (P> 0.05). CONCLUSION: Estrogen removal obviously damages learning and memory in mice and estrogen replacement can improve learning and memory in OVX mice. But over load of estrogen had no effects on processing of learning and memory in normal mice.