Effect of oral morphine and naloxone on pituitary-adrenal response in man induced by human corticotropin-releasing hormone.
To further investigate the role of opioids in the regulation of the pituitary-adrenal axis we studied the effect of morphine and naloxone on human corticotropin-releasing hormone (hCRH)-induced ACTH, immunoreactive (ir) beta-endorphin, and cortisol release in normal subjects. Protocols: 1. 30 mg of a slow-release preparation of morphine or placebo was given orally 3 h prior to administration of hCRH (0.1 mg iv) (N = 7). 2. Naloxone (4 mg as bolus iv) or placebo was given 5 min prior to hCRH (N = 7). 3. Naloxone (4 mg iv as bolus followed by a continuous infusion of 6 mg over 75 min) or placebo was started 15 min prior to hCRH (N = 6). hCRH was injected at 11.00 h (protocol 1, 2) or at 17.00 h (protocol 3). Oral morphine not only suppressed basal hormone levels (P less than 0.02), but also the peak response to hCRH compared with placebo (cortisol: 270 +/- 50 vs 559 +/- 80 nmol/l; ACTH: 5.1 +/- 1.5 vs 13.1 +/- 2.7 pmol/l; ir beta-endorphin: 48.5 +/- 8.7 vs 88 +/- 14 pmol/l; mean +/- SEM, P less than 0.02). Similarly, the maximum incremental changes and the area under the curve were significantly reduced for all three hormones compared with placebo (P less than 0.05). After 4 mg of naloxone in the morning, no significant hormonal changes in response to hCRH were observed.(ABSTRACT TRUNCATED AT 250 WORDS)
D000284:Administration, Oral; D000324:Adrenocorticotropic Hormone / Q000378:metabolism; D000328:Adult; D003346:Corticotropin-Releasing Hormone / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004723:Endorphins / Q000378:metabolism; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009020:Morphine / Q000008:administration & dosage*; D009270:Naloxone / Q000008:administration & dosage*; D010913:Pituitary-Adrenal System / Q000187:drug effects*; D011388:Prolactin / Q000378:metabolism; D001615:beta-Endorphin
D004723:Endorphins; D009270:Naloxone; D001615:beta-Endorphin; D009020:Morphine; D000324:Adrenocorticotropic Hormone; D011388:Prolactin; D003346:Corticotropin-Releasing Hormone; D006854:Hydrocortisone