[The role of hormones of hypothalamic-pituitary-adrenocortical system in analgesic effect of corticotropin-releasing hormone].

The role of hypothalamic-pituitary-adrenocortical system (HPAS) in analgesic effect induced by central or systemic corticotrophin-releasing hormone (CRH) was studied on anaesthetized male rats. Blockade of the HPAS functional activity by hydrocortisone in pharmacological dose one week before the experiment was used as approach to investigate the contribution of the HPAS hormones in CRF-induced analgesia. Elimination of the hormones rise in the blood plasma by hydrocortisone resulted in decrease of analgesic effect induced by systemic CHR and complete disappearance of analgesic effect induced by central CRH. The results suggest that CRH-induced elevation of pain threshold is provided by two components: 1) depending on the HPAS hormones after central and systemic injection of CHR; 2) not depending on the HPAS hormones after systemic injection of CHR.