Effect of morphine on hypothalamic corticotropin-releasing factor (CRF) and pituitary-adrenocortical activity.
The effects of intraperitoneal and intra-third ventricular administration of morphine on the hypothalamic corticotropin-releasing factor (CRF) and the pituitary-adrenocortical activity were examined in unanesthetized, freely moving rats. Hypothalamic CRF was measured by rat CRF radioimmunoassay. Intraperitoneal or intra-third ventricular administration of morphine increased blood concentrations of ACTH and corticosterone while intraperitoneal administration tended to increase CRF concentration in the whole hypothalamus including the median eminence and intra-third ventricular administration increased CRF concentration in the hypothalamus excluding the median eminence. However, morphine seemed to inhibit the increase in CRF concentration in the hypothalamus induced by the ether-laparotomy stress. The main site of morphine action on the hypothalamo-pituitary-adrenocortical system seemed to be in the hypothalamic area.
D000324:Adrenocorticotropic Hormone / Q000097:blood; D000818:Animals; D003345:Corticosterone / Q000097:blood; D003346:Corticotropin-Releasing Hormone / Q000378:metabolism*; D007031:Hypothalamus / Q000187:drug effects*; D007274:Injections, Intraperitoneal; D007276:Injections, Intraventricular; D008297:Male; D009020:Morphine / Q000008:administration & dosage / Q000494:pharmacology*; D010913:Pituitary-Adrenal System / Q000187:drug effects*; D051381:Rats; D011919:Rats, Inbred Strains
D009020:Morphine; D000324:Adrenocorticotropic Hormone; D003346:Corticotropin-Releasing Hormone; D003345:Corticosterone