Ohashi Y, Okamoto N, Uchida K, Iyo M, Mori N, Morita Y
Department of Psychiatry and Neurology, Hamamatsu University School of Medicine, Japan.
Biol Signals. 1997 Jul-Dec;6(4-6):301-6. doi: 10.1159/000109141.
The daily profile of serum level of melatonin was studied in 10 young and 13 elderly subjects. All of the subjects were physically and psychiatrically healthy and did not have any clinical symptoms related to rhythm disturbance. Blood samples were taken every 3 h for 1 day and serum melatonin levels were determined by RIA. All except for 1 of the elderly subjects exhibited a clear circadian rhythm of serum melatonin level with a nocturnal peak. In both subject groups, the melatonin rhythm showed significant diurnal variation. There was no significant difference in the total melatonin level per day between young and elderly groups, suggesting that there was no influence of aging on daily total melatonin secretion. However, there was a marked difference in the features of the melatonin rhythm between the two groups, i.e., a rapid decline of the melatonin level from the nocturnal peak in the elderly group, suggesting that the off-set time of melatonin secretion advances with aging. Our findings suggest that the pattern of melatonin rhythm alters significantly without clear clinical symptoms in the process of senescence.
对10名年轻受试者和13名老年受试者的血清褪黑素水平的每日变化情况进行了研究。所有受试者身体和精神健康，没有任何与节律紊乱相关的临床症状。连续1天每3小时采集一次血样，采用放射免疫分析法测定血清褪黑素水平。除1名老年受试者外，其他所有老年受试者的血清褪黑素水平均呈现明显的昼夜节律，且夜间达到峰值。在两个受试者组中，褪黑素节律均表现出显著的日间变化。年轻人组和老年人组每天的褪黑素总量没有显著差异，这表明衰老对每日褪黑素的总分泌量没有影响。然而，两组之间褪黑素节律的特征存在明显差异，即老年组中褪黑素水平从夜间峰值迅速下降，这表明褪黑素分泌的偏移时间随着衰老而提前。我们的研究结果表明，在衰老过程中，褪黑素节律模式会发生显著改变，且无明显临床症状。
