title: Naloxone inhibition of postprandial growth hormone releasing hormone-induced growth hormone release in obesity.
abstract: The effects of opiate receptor antagonist naloxone on growth hormone (GH) release after growth hormone-releasing hormone (GHRH) administration were investigated, before or after feeding, at 13.00 h, in 20 obese women and in 10 normal women. When GHRH was administered to obese women before a meal at lunch time, the mean peak plasma GH levels were very low, while plasma GH responses significantly increased after feeding. Naloxone, infused at a rate of 1.6 mg/h starting 1 h before GHRH administration (50 micrograms i.v. as a bolus), was capable of inhibiting GH release induced by administration of GHRH after feeding. On the contrary, naloxone did not induce significant variations on the fasting GHRH-induced GH release. In normal women, naloxone did not significantly modify the GH response to GHRH, both before and after lunch. The inhibitory effect of naloxone indicates that in obese women there is an increased opioid activity, which could represent an abnormal response of the gastrointestinal tract to food ingestion.
authors.affiliation: Institute of Endocrinology, Catholic University School of Medicine, Rome, Italy.
authors.forename: L
authors.initials: L
authors.lastname: De Marinis
authors.forename: A
authors.initials: A
authors.lastname: Mancini
authors.forename: G
authors.initials: G
authors.lastname: Folli
authors.forename: C
authors.initials: C
authors.lastname: D'Amico
authors.forename: S M
authors.initials: SM
authors.lastname: Corsello
authors.forename: R
authors.initials: R
authors.lastname: Sciuto
authors.forename: A
authors.initials: A
authors.lastname: Tofani
authors.forename: P
authors.initials: P
authors.lastname: Sambo
authors.forename: A
authors.initials: A
authors.lastname: Barbarino
mesh_terms: D000328:Adult; D004435:Eating; D005260:Female; D013006:Growth Hormone / Q000378:metabolism*; D013007:Growth Hormone-Releasing Hormone / Q000502:physiology*; D006801:Humans; D009270:Naloxone / Q000494:pharmacology*; D009765:Obesity / Q000503:physiopathology*; D011957:Receptors, Opioid / Q000187:drug effects
chemical_list: D011957:Receptors, Opioid; D009270:Naloxone; D013006:Growth Hormone; D013007:Growth Hormone-Releasing Hormone