Aedo A R, Nuñez M, Landgren B M, Cekan S Z, Diczfalusy E
Acta Endocrinol (Copenh). 1977 Feb;84(2):320-32. doi: 10.1530/acta.0.0840320.
Circadian variations of the plasma levels of dehydroepiandrosterone, 17-hydroxypregnenolone, pregnenolone and testosterone were investigated by radioimmunoassay in 10 normally menstruating women during the periovulatory period. In seven of the subjects it was also possible to estimate androstenedione and dihydrotestosterone levels. Blood was withdrawn continuously over a period of 48 h at a rate of 4 ml/h by means of a non-thrombogenic pump. The circadian rhythm was studied during 13 3-hour sampling periods (36 h) which were identical in all subjects. Dehydroepiandrosterone, 17-hydroxypregnenolone and pregnenolone showed a marked circadian rhythm with highest mean levels in the morning between 06.00 and 0.900 h and lowest mean levels during the night between 21.00 and 24.00 h. The peak levels of individual subjects coincided completely with the highest mean levels in the case of dehydroepiandrosterone, in 9 out of 10 cases with regard to 17-hydroxypregnenolone and in 8 of 10 cases as far as pregnenolone levels were concerned. The lowest individual levels were more dispersed around the means than were the individual peaks. The difference between the highest (morning hours: 06.00-09.00) and lowest (evening hours: 21.00-24.00) geometeric mean values was 404% for 17-hydroxypregnenolone, 163% for dehydroepiandrosterone and 71% for pregnenolone. The mean testosterone levels also exhibited an elevation between 06.00 and 09.00 h which was significant (P less than 0.05). However, the individual peak values were scattered from 21.00 h of the first day to 18.00 h of the second day. The mean concentrations of androstendine showed a significant increase between 06.00 and 18.00 h. The individual peaks were widely dispersed. Hence a uniform circadian rhythm correlated to the levels of the 5-steroids mentioned above could not be demonstrated in the case of testosterone and androstenedione. An analysis of variance indicated no significant differences between sampling periods as far as dihydrotestosterone levels were concerned. The extent and regularity of the circadian variation in the plasma levels of the 5-steroids studied makes it mandatory to standardize very carefully the exact time of blood withdrawal in any longitudinal study. In view of the sharp changes in the plasma levels during the morning hours, it is suggested that sampling during the afternoon period may provide more constant values.
采用放射免疫分析法，对10名月经周期正常的女性在排卵期前后血浆中脱氢表雄酮、17-羟孕烯醇酮、孕烯醇酮和睾酮水平的昼夜变化进行了研究。其中7名受试者还测定了雄烯二酮和双氢睾酮水平。通过非血栓形成泵以4ml/h的速率在48小时内连续采血。在所有受试者相同的13个3小时采样时段（共36小时）内研究昼夜节律。脱氢表雄酮、17-羟孕烯醇酮和孕烯醇酮呈现明显的昼夜节律，上午06:00至09:00平均水平最高，夜间21:00至24:00平均水平最低。就脱氢表雄酮而言，个体峰值水平与最高平均水平完全一致；17-羟孕烯醇酮在10例中有9例如此；孕烯醇酮水平在10例中有8例是这样。个体最低水平围绕均值的离散度比个体峰值大。17-羟孕烯醇酮最高（上午时段：06:00 - 09:00）与最低（傍晚时段：21:00 - 24:00）几何均值之差为404%，脱氢表雄酮为163%，孕烯醇酮为71%。睾酮平均水平在06:00至09:00之间也有升高，差异有统计学意义（P<0.05）。然而，个体峰值时间从第一天的21:00到第二天的18:00分散分布。雄烯二酮平均浓度在06:00至18:00之间有显著升高，个体峰值广泛分散。因此，在睾酮和雄烯二酮的情况下，未能证明与上述5种甾体激素水平相关的统一昼夜节律。方差分析表明，就双氢睾酮水平而言，各采样时段之间无显著差异。所研究的5种甾体激素血浆水平昼夜变化的程度和规律性表明，在任何纵向研究中，必须非常仔细地规范采血的确切时间。鉴于上午时段血浆水平变化剧烈，建议下午采样可能会得到更稳定的值。
