Pattern of plasma pregnenolone sulfate levels in humans from birth to adulthood.

Plasma levels of pregnenolone sulfate (PS) were measured in 659 normal subjects whose age ranged from birth to adulthood. PS levels were similar in both sexes. At birth PS values (mean +/- 1 SD) were very high, 109.7 +/- 49 micrograms/dl in mixed cord plasma of 50 neonates, and they were 86 +/- 38.7 micrograms/dl in peripheral plasma during the first day of life in 52 babies. During the first month of life, PS levels decreased to mean values of 53.8 +/- 31.3 micrograms/dl in infants aged 2-30 days, 11.1 +/- 7.9 micrograms/dl between 4 and 6 months, and 3.7 +/- 2.8 micrograms/dl between 7 and 12 months of life. PS values were very low during the second year (1.7 +/- 1.6 micrograms/dl) and remained low through the ninth year of life. A progressive rise was then found until adulthood. The values in adults (5.3 +/0- 2.6 micrograms/dl) were 3 to 4 times higher than between 1 and 9 yr of life but 20 times lower than in cord plasma. This pattern of evolution is in contrast with that of DHAS which rose abruptly at the seventh year of life at the time of the adrenarche. PS therefore does not contribute to the adrenarche. The changes induced by adrenal stimulation and suppression and by testicular stimulation were also studied. Plasma PS levels rose after either acute or long term stimulation with ACTH and were suppressed by dexamethasone, as were cortisol levels in the same tests. A very close correlation was found between the rise of PS and ACTH levels at the end of metyrapone tests. In contrast gonadal participation in the production of PS was moderate. These results suggest that the measurement of PS could be a good index of ACTH production in children.