NOCTURNAL ACTH, CORTISOL, GROWTH-HORMONE, AND PROLACTIN SECRETION IN PREPUBERTAL DEPRESSION

Objective: To examine nocturnal secretion of adrenocorticotropin, cort isol, growth hormone, and prolactin in 38 medically healthy children w ith prepubertal major depression compared with 28 medically and psychi atrically healthy control children. Method: Prior to sampling, subject s underwent an ''adaptation night'' with the intravenous catheter in p lace and electroencephalographic (EEG) electrodes for standard all-nig ht polysomnogram. On the following night, plasma samples were obtained every PO minutes through an indwelling catheter. Hormonal concentrati ons were measured by specific radioimmunoassay and aligned by EEG-conf irmed sleep onset. Areas under the curve were calculated for total sec retion and compared using analysis of variance. Results: Prepubertal d epressed children had lower cortisol secretion during the first 4 hour s after sleep onset compared with controls. Adrenocorticotropin, prola ctin, and growth hormone secretion did not differ between groups. Exam ination of clinical characteristics in depressed children revealed low er nocturnal adrenocorticotropin concentrations in depressed inpatient s versus depressed outpatients and in depressed sexually abused Versus depressed nonabused children. A significant sex by diagnosis effect r evealed lower growth hormone secretion in depressed females compared w ith depressed males. Conclusions: In contrast to neuroendocrine challe nge studies in these same subjects, noctumal neuroendocrine measures d id not reveal any of the expected group differences. These results emp hasize the contrasts between unstimulated and challenge studies of neu roendocrine secretion and of the importance of considering clinical ch aracteristics and maturation influences in biological studies of prepu bertal depression.