Laakso M L, Porkka-Heiskanen T, Alila A, Stenberg D, Johansson G
Department of Physiology, University of Helsinki, Finland.
J Pineal Res. 1990;9(1):39-50. doi: 10.1111/j.1600-079x.1990.tb00692.x.
Saliva and serum samples were collected from eight healthy volunteers every two hours during a 26-hour period. Melatonin concentrations were measured by radioimmunoassay after chloroform extraction using radioiodinated melatonin as a tracer. Five of the subjects had high serum melatonin levels at night (peak levels higher than 75 pg/ml); in three subjects the highest serum melatonin concentration was 20-40 pg/ml. All subjects had low levels (less than 10 pg/ml) during the day. The correlations between salivary and serum levels were calculated. The regression line y = 0.33x + 3.7 pg/ml, r = 0.95, P less than 0.001, was obtained for all detectable value pairs (n = 73). The regression and correlation coefficients were almost equal for the peak values of melatonin and during the rising and descending phases of the secretion patterns. However, no significant correlation was found between low daytime salivary and serum concentrations when calculated separately. In the five high-secretors the melatonin levels in saliva reflected reliably the changes in serum, but in the three low-secretors the correlation between salivary and serum melatonin was not significant. The proportion of melatonin found in saliva decreased with increasing serum melatonin levels. Circadian rhythm parameters were estimated by single cosinor analysis. The acrophases did not differ significantly within a subject in the concomitant measurements of serum and salivary melatonin. The measurements of salivary melatonin levels seem valid for studies on melatonin rhythms, but the melatonin concentrations measured in saliva do not always consistently reflect the absolute concentrations in blood.
在26小时内，每两小时从8名健康志愿者身上采集唾液和血清样本。使用放射性碘化褪黑素作为示踪剂，经氯仿萃取后，通过放射免疫分析法测定褪黑素浓度。5名受试者夜间血清褪黑素水平较高（峰值水平高于75 pg/ml）；3名受试者血清褪黑素最高浓度为20 - 40 pg/ml。所有受试者白天水平较低（低于10 pg/ml）。计算唾液和血清水平之间的相关性。对于所有可检测值对（n = 73），得到回归线y = 0.33x + 3.7 pg/ml，r = 0.95，P小于0.001。褪黑素峰值以及分泌模式的上升和下降阶段，回归系数和相关系数几乎相等。然而，分别计算时，白天唾液和血清低浓度之间未发现显著相关性。在5名高分泌者中，唾液中的褪黑素水平可靠地反映了血清中的变化，但在3名低分泌者中，唾液和血清褪黑素之间的相关性不显著。唾液中发现的褪黑素比例随血清褪黑素水平升高而降低。通过单余弦分析估计昼夜节律参数。在同时测量血清和唾液褪黑素时，同一受试者内的峰相位无显著差异。唾液褪黑素水平的测量对于褪黑素节律研究似乎有效，但唾液中测得的褪黑素浓度并不总是一致地反映血液中的绝对浓度。
