Developmental patterns of serum luteinizing hormone, gonadal and adrenal steroids in the sooty mangabey (Cercocebus atys).

Serum levels of luteinizing hormone (LH), testosterone, dehydroepiandrosterone sulfate (DHAS), androstenedione and cortisol were determined in multiple samples from 86 sooty mangabeys of varying ages (0-17 years). Testosterone, androstenedione, DHAS and cortisol were measured by radioimmunoassay; LH was determined by in vitro bioassay. Serum LH concentrations were elevated in neonates (less than 6 months) and in animals older than 72 months of age. The higher LH levels were associated with increased circulating concentrations of testosterone in males but not females. The pubertal rise in serum testosterone at approximately 55-60 months of age in males was coincident with rapid body growth. No pubertal growth spurt was observed in females. Serum levels of androstenedione and DHAS were highest during early postnatal life (less than 6 months) with androstenedione exceeding 600 ng/dl in males and 250 micrograms/dl in females, but declined rapidly in both sexes to a baseline of 150 ng/dl by 19 months of age. Serum androstenedione did not fluctuate significantly in adult animals. The pattern of age-related changes in serum DHAS paralleled those of serum androstenedione, whereas serum cortisol values did not change significantly with age. Developmental changes in serum LH, testosterone and body weight suggest that the sooty mangabey matures substantially later than the rhesus monkey. The pattern of serum gonadal and adrenal steroids during sexual maturation is similar to that seen in the baboon with no evidence of an adrenarche.