Fader A J, Hendricson A W, Dohanich G P
Department of Psychology, Tulane University, New Orleans, Louisiana, 70118, USA.
Neurobiol Learn Mem. 1998 May;69(3):225-40. doi: 10.1006/nlme.1998.3820.
In a previous study, administration of high doses of estradiol benzoate (100 microgram/kg for 3 days im) to ovariectomized Long-Evans rats counteracted impairments of reinforced T-maze alternation induced by systemic administration of scopolamine, a muscarinic receptor blocker. In the current study, daily administration of lower doses of estradiol benzoate (5 microgram/kg for 3 weeks sc) increased the number of correct reinforced alternations during T-maze acquisition in ovariectomized rats compared to oil-treated controls and prevented impairments of reinforced alternation induced by injection of scopolamine hydrobromide (0.2 mg/kg ip). Furthermore, scopolamine (20 microgram) delivered bilaterally to the dorsal hippocampus reduced reinforced T-maze alternation in ovariectomized rats previously trained to complete this task while daily treatment with estradiol benzoate (5 microgram/kg sc) for 1 week prior to scopolamine infusion counteracted this impairment. In summary, physiological levels of estrogen improved performance during acquisition of reinforced T-maze alternation and prevented impairments induced by scopolamine administered systemically or intrahippocampally.
在先前的一项研究中，给去卵巢的Long-Evans大鼠注射高剂量苯甲酸雌二醇（100微克/千克，腹腔注射3天），可对抗由毒蕈碱受体阻滞剂东莨菪碱全身给药所诱导的强化T迷宫交替任务的损伤。在当前研究中，与油处理的对照组相比，给去卵巢大鼠每日注射较低剂量的苯甲酸雌二醇（5微克/千克，皮下注射3周）可增加T迷宫训练期间正确强化交替的次数，并预防由注射氢溴酸东莨菪碱（0.2毫克/千克，腹腔注射）所诱导的强化交替损伤。此外，双侧背侧海马注射东莨菪碱（20微克）可降低先前已训练完成此任务的去卵巢大鼠的强化T迷宫交替，而在注入东莨菪碱前1周每日用苯甲酸雌二醇（5微克/千克，皮下注射）治疗可对抗这种损伤。总之，生理水平的雌激素可改善强化T迷宫交替训练期间的表现，并预防全身或海马内注射东莨菪碱所诱导的损伤。
