title: The effect of a met-enkephalin analogue on growth hormone, prolactin, gonadotropins, cortisol and thyroid stimulating hormone in healthy elderly men.
abstract: The aim of the study was to evaluate the effect of the guanyl derivative of the opioid analogue D-ala2,MePhe4-Met-enkephalin-(o)-ol (G-DAMME) on pituitary secretion in healthy elderly men. Nine healthy elderly men (65-88 years) and 10 young adults (20-30 years) were studied. GH, PRL, gonadotropins, cortisol (to evaluate the effect on ACTH) and TSH were measured after G-DAMME (0.25 mg iv) or placebo administration. In elderly men, the GH response to G-DAMME was reduced or absent, while prompt GH release was found in all young men. G-DAMME lowered LH levels in young men but not in elderly men. No significant variations in FSH levels after G-DAMME and placebo were noted in either group of subjects. A similar and significant rise in PRL and TSH, and a fall in cortisol, after G-DAMME was observed in both elderly and young adults. We have demonstrated that the sensitivity to opioid modulation by G-DAMME on PRL, TSH and cortisol secretion is unchanged with aging. On the other hand, the data indicate that LH and GH responsiveness to G-DAMME change with age.
authors.affiliation: DISEM, Cattedra di Endocrinologia, Università di Genova, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Giusti
authors.forename: G
authors.initials: G
authors.lastname: Delitala
authors.forename: G
authors.initials: G
authors.lastname: Marini
authors.forename: B
authors.initials: B
authors.lastname: Uggias
authors.forename: P
authors.initials: P
authors.lastname: Sessarego
authors.forename: G M
authors.initials: GM
authors.lastname: Besser
authors.forename: A
authors.initials: A
authors.lastname: Grossman
authors.forename: G
authors.initials: G
authors.lastname: Giordano
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005405:D-Ala(2),MePhe(4),Met(0)-ol-enkephalin / Q000494:pharmacology*; D004744:Enkephalin, Methionine / Q000031:analogs & derivatives*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D008297:Male; D010902:Pituitary Gland / Q000378:metabolism; D010907:Pituitary Hormones / Q000097:blood*
chemical_list: D010907:Pituitary Hormones; D004744:Enkephalin, Methionine; D005405:D-Ala(2),MePhe(4),Met(0)-ol-enkephalin; D006854:Hydrocortisone