Kubanis P, Zornetzer S F, Freund G
Pharmacol Biochem Behav. 1982 Aug;17(2):313-22. doi: 10.1016/0091-3057(82)90086-7.
Significant retention deficits were observed on passive avoidance tasks (step-down and step-through) in 15-, 20-, and 25-month-old male C57BL/6 mice compared with 4- and 8-month-old mice. In contrast, cholinergic muscarinic receptor binding ( [3H]quinuclidinyl benzilate) in cerebral cortex, striatum, hippocampus, and cerebellum in these same animals revealed no difference in this 4- to 25-month age range. In a separate comparison of 4- and 29-month-old female mice, [3H]QNB binding was significantly decreased in the older group in cerebral cortex, hippocampus, and striatum. Environmental enrichment, compared with an impoverished environment, significantly improved retention in mice on 24-hr step-down performance but affected QNB binding only minimally (6-7% decrease of QNB binding in cerebral cortex and hippocampus). Benzodiazepine ( [3H]flunitrazepam) receptor binding was significantly (12-15%) decreased in 29-month-old mice compared with 4-month-old mice in the cerebral cortex, hippocampus, cerebellum, and brain stem.
与4个月和8个月大的雄性C57BL/6小鼠相比，在15个月、20个月和25个月大的雄性C57BL/6小鼠的被动回避任务（跳下和穿过）中观察到显著的记忆缺陷。相比之下，在这4至25个月的年龄范围内，这些相同动物的大脑皮质、纹状体、海马体和小脑中的胆碱能毒蕈碱受体结合（[3H]喹核醇基苯甲酸酯）没有差异。在对4个月和29个月大的雌性小鼠的单独比较中，老年组的大脑皮质、海马体和纹状体中的[3H]QNB结合显著降低。与贫乏环境相比，丰富环境显著改善了小鼠在24小时跳下实验中的记忆，但对QNB结合的影响最小（大脑皮质和海马体中QNB结合减少6 - 7%）。与4个月大的小鼠相比，29个月大的小鼠的大脑皮质、海马体、小脑和脑干中的苯二氮䓬（[3H]氟硝西泮）受体结合显著降低（12 - 15%）。
