Do the suprachiasmatic nuclei oscillate in old rats as they do in young ones?
Do the suprachiasmatic nuclei oscillate in old rats as they do in young ones?
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年老大鼠的视交叉上核是否像年轻大鼠那样振荡？
DOI：
10.1152/ajpregu.1993.265.5.r1216
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Gillette,MU
中科院分区：
文献类型：
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作者：
Satinoff,E;Li,H;Tcheng,TK;Liu,C;McArthur,AJ;Medanic,M;Gillette,MU
通过比较年轻和年老大鼠的三种行为节律模式与主要昼夜节律起搏器视交叉上核（SCN）神经元活动的体外节律，揭示了昼夜节律随衰老而下降的基础。在一些老年大鼠中，体温、饮水和活动的节律在明暗循环中保留了显着的 24 小时周期性；在其他情况下，一两个节奏变得非周期性。当这些大鼠23-27.5个月大时，将其处死，并连续记录SCN脑切片中的单单位放电率30小时。与年轻大鼠相比，老年大鼠的平均峰值神经元放电率显着减弱。还参考个体大鼠之前的行为节律模式来分析 SCN 神经元活动。正如预期的那样，先前具有非周期性行为节律的大鼠的神经元活动不稳定。被处死时仍保持显着 24 小时行为节律的大鼠的神经元活动在大多数情况下不稳定，但在其他情况下则正常节律。因此，行为节律和脑切片节律之间的一致性并不比单独的行为节律之间的一致性高。这些结果首次证明老年大鼠存在异常的 SCN 放电模式和振幅降低，这意味着衰老可能会破坏 SCN 起搏细胞或其输出之间的耦合，或者导致 SCN 细胞的起搏特性恶化。
The basis of the decline in circadian rhythms with aging was addressed by comparing the patterns of three behavioral rhythms in young and old rats with the in vitro rhythm of neuronal activity in the suprachiasmatic nuclei (SCN), the primary circadian pacemaker. In some old rats, rhythms of body temperature, drinking, and activity retained significant 24-h periodicities in entraining light-dark cycles; in others, one or two of the rhythms became aperiodic. When these rats were 23-27.5 mo old they were killed, and single-unit firing rates in SCN brain slices were recorded continuously for 30 h. There was significant damping of mean peak neuronal firing rates in old rats compared with young. SCN neuronal activities were analyzed with reference to previous entrained behavioral rhythm patterns of individual rats as well. Neuronal activity from rats with prior aperiodic behavioral rhythms was erratic, as expected. Neuronal activity from rats that were still maintaining significant 24-h behavioral rhythmicity at the time they were killed was erratic in most cases but normally rhythmic in others. Thus there was no more congruence between the behavioral rhythms and the brain slice rhythms than there was among the behavioral rhythms alone. These results, the first to demonstrate aberrant SCN firing patterns and a decrease in amplitude in old rats, imply that aging could either disrupt coupling between SCN pacemaker cells or their output, or cause deterioration of the pacemaking properties of SCN cells.