Corticotropin releasing hormone increases apparent potency of adrenocorticotropic hormone stimulation of cortisol secretion

Hypothesis: Corticotropin releasing hormone (CRH) has a regulatory effect o n cortisol secretion in addition to its classic effect of stimulating adren ocorticotropic hormone (ACTH) secretion. Review: There is growing evidence of 'long-loop' and paracrine adrenal stimulation by CRH. Data from a study of the ovine-corticotropin releasing hormone (oCRH) stimulation test in 13 sexually abused girls and 13 normal controls was used in Montecarlo simulat ions of the hypothalamic-pituitary-adrenal axis, to get estimates of adrena l sensitivity to ACTH and cortisol elimination kinetics before and after oC RH administration. In both controls and sexually abused girls, ACTH had an apparent greater effect on cortisol secretion after administration of oCRH compared to its effect during the baseline period. This lends support to th e hypothesis and suggests that it should be tested experimentally. (C) 2001 Harcourt Publishers Ltd.