The Nocturnal Rise of Plasma Testosterone in Pubertal Boys.

To evaluate the effect on testicular function of the sleep related LH rise in pubertal subjects, identical twin boys (JA-1; JA-2) in stage 2 of puberty were studied for 36 hours using a frequent sampling technique. While each subject was awake the mean ± S.E. testosterone (T) level was 257 ± 41 and 325 ± 31 pg/ml for JA-1 and JA-2 respectively. Each night with the commencement of sleep, sharp increases of T and LH but not FSH levels occurred. The nocturnal elevations of T reached peaks of 1887 and 1833 pg/ml for the same respective subjects and were always preceded by the sleep related LH rises. The interval between the nocturnal LH r i se and the beginning of the subsequent T elevation was 40-80 minutes. This data suggests that in adolescent boys the sleep related LH increase stimulates a nocturnal rise of T. This androgen increase could account for some of the early pubertal changes seen in males.