Aging alters the circadian rhythm of glucose utilization in the suprachiasmatic nucleus.
Aging alters the circadian rhythm of glucose utilization in the suprachiasmatic nucleus.
复制标题
衰老改变了视交叉上核葡萄糖利用的昼夜节律。
DOI：
10.1073/pnas.85.14.5305
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发表时间：
1988
影响因子：
11.1
通讯作者：
London,ED
中科院分区：
文献类型：
--
作者：
Wise,PM;Cohen,IR;Weiland,NG;London,ED
我们研究了中年向不孕症转变过程中周期黄体生成素(LH)释放时间的变化是否反映了下丘脑起搏器区域，特别是视交叉上核神经功能的昼夜模式的不同。我们测量了局部脑葡萄糖利用率(LCGU)，因为这一参数是局部脑功能的指标。我们评估了年轻和中年去卵巢的雌激素治疗大鼠的几个脑区的LCGU，因为当大鼠到中年时，黄体生成素峰值会改变。这种改变与调节黄体生成素循环释放的几个下丘脑区域的神经递质周转的昼夜模式的变化有关。这些数据显示了视交叉上核背侧和腹侧葡萄糖利用的昼夜节律。在幼年大鼠中，LCGU在点灯后1小时内增加，在黄体生成素峰开始前进一步增加，并在关灯后1小时内下降。相比之下，中年大鼠在开灯后LCGU表现出更缓慢的增加，在黄体生成素激增之前没有进一步增加，下午和晚上过早下降。结果提示，中年大鼠LCGU昼夜节律的改变可能与雌二醇性黄体生成素诱发的黄体生成素高峰的时间和幅度改变有关。生物钟的完整性或生物钟携带其他神经化学事件的能力的变化可能是周期性生殖功能改变和向不规则发情周期转变的基础。
We examined the possibility that alterations in the timing of cyclic luteinizing hormone (LH) release during the middle age transition to infertility reflect differences in the circadian pattern of neural function in pacemaker areas of the hypothalamus, particularly the suprachiasmatic nucleus. We measured local cerebral glucose utilization (LCGU) because this parameter is an index of local brain function. We assessed LCGU in several brain areas of young and middle-aged ovariectomized estradiol-treated rats since LH surges are altered when rats are middle-aged. This alteration is correlated with changes in the diurnal pattern of neurotransmitter turnover in several hypothalamic areas that regulate cyclic LH release. The data demonstrate a circadian rhythm in glucose utilization in the dorsal and ventral suprachiasmatic nucleus. In young rats, LCGU increases within 1 hr of lights-on, increases further just prior to the initiation of the LH surge, and decreases within 1 hr of lights-off. In contrast, middle-aged rats show a more gradual increase in LCGU after lights-on, with no further increase prior to the LH surge, and a premature decrease during the afternoon and evening. The data suggest that changes in the circadian pattern of LCGU may be related to the alteration in timing and amplitude of estradiol-induced LH surges in middle-aged rats. Changes in the integrity of the biological clock or in the ability of the biological clock to entrain other neurochemical events may underlie the onset of altered cyclic reproductive function and the transition to irregular estrous cyclicity.