Daniel Jill M, Winsauer Peter J, Moerschbaecher Joseph M
Department of Pharmacology and Experimental Therapeutics, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA.
Department of Psychology, University of New Orleans, New Orleans, LA 70148, USA.
Psychopharmacology (Berl). 2003 Nov;170(3):294-300. doi: 10.1007/s00213-003-1537-4. Epub 2003 Jul 25.
Although much research has focused on the effects of ovarian hormones on learning and memory in females, less information is available regarding the effects of testicular hormones on learning and memory in males. Additionally, despite evidence of an interaction of testicular hormones and the cholinergic system in areas of the brain implicated in learning and memory, no information is available regarding the behavioral consequences of that interaction.
We assessed the effect of castration in male rats on working memory during acquisition of a radial maze. We also assessed the interactive effects of castration and scopolamine, a muscarinic receptor antagonist, as well as mecamylamine, a nicotinic receptor antagonist, on behavior.
Young adult male rats were castrated or underwent sham surgeries. Beginning 10 days after surgeries, performance on a task of working memory was assessed across 24 days of acquisition in an eight-arm radial maze. Following acquisition, scopolamine and mecamylamine dose-effect curves were established.
Castration of male rats significantly decreased arm-choice accuracy during acquisition. Castration significantly exacerbated impairments in arm-choice accuracy produced by scopolamine as well as mecamylamine, without altering the disruptive effects of the drugs on the rate at which rats entered the arms of the maze.
These results indicate that castration in male rats impairs working memory during acquisition of a spatial maze task. Additionally, these results suggest that the absence of testicular hormones increases the sensitivity of male rats to the impairing effects of scopolamine as well as mecamylamine on working memory.
尽管许多研究聚焦于卵巢激素对雌性动物学习和记忆的影响，但关于睾丸激素对雄性动物学习和记忆的影响，所知甚少。此外，尽管有证据表明睾丸激素与大脑中涉及学习和记忆的区域的胆碱能系统存在相互作用，但关于这种相互作用的行为后果尚无相关信息。
我们评估了雄性大鼠去势对放射状迷宫学习过程中工作记忆的影响。我们还评估了去势与毒蕈碱受体拮抗剂东莨菪碱以及烟碱受体拮抗剂美加明对行为的交互作用。
成年雄性幼鼠接受去势手术或假手术。术后10天开始，在八臂放射状迷宫中，通过24天的学习过程评估工作记忆任务的表现。学习完成后，确定东莨菪碱和美加明的剂量效应曲线。
雄性大鼠去势显著降低了学习过程中的臂选择准确性。去势显著加剧了东莨菪碱和美加明导致的臂选择准确性损伤，且未改变药物对大鼠进入迷宫臂的速度的干扰作用。
这些结果表明，雄性大鼠去势会损害空间迷宫任务学习过程中的工作记忆。此外，这些结果表明，缺乏睾丸激素会增加雄性大鼠对东莨菪碱和美加明对工作记忆的损害作用的敏感性。
