【摘要】 本文从下丘脑、大脑皮层、海马等脑区去甲肾上腺素（NA）的含量,其合成酶与降解酶的活性、NA受体数目等多环节的测定来分析肾上腺素能神经递质系统在老化脑中的变化。实验结果表明衰老过程下丘脑、大脑皮层内NA合成酶活性没变化,NA含量明显增高,下丘脑内α₁受体数目显著减少。上述结果提示这些脑区肾上腺素能神经的活动有可能减弱。同时,海马内单胺氧化酶B（MAO B）活性明显增加,说明海马神经元外组织有增生的可能。泰文并讨论了这些变化与老年记忆、行为与神经内分泌等脑功能衰退的关系。更多还原

【Abstract】 The influence of age on the concentration, synthesis and metabolism of noradrenaline(NA)and its receptors in different areas of brain was studied. It was found that the content of NA in hypothalamus and cortex was much higher in the aged rats than that in young, while the activity of its synthetase (DBH) had no change. In addition, there was a significant decrease in the density of alpha 1 adrenoceptor in aged rats. We suggested that the release of NA in hypothalamus and cortex was probably reduced, and the adrenergic neuronal activity was impaired during aging. This impairment may initiate or contribute to the age-related dysfunction of memory, ehaviors and neuroendocrine. Meantime, the activity of monoamine oxidase in hippocampus of aged rats was significantly higher than that in young rats, this might be attributed to the neuronal loss and glia cell proliferatioin hippocampus which plays a very important role in memory function during aging.更多还原