title: Naloxone decreases the inhibitory effect of somatostatin on GH release induced by cigarette smoking in man.
abstract: To establish whether somatostatin (SRIH) exerts its inhibitory effect on the nicotine-induced release of GH by interacting with an opioid pathway, normal volunteers were treated with naloxone during (2 no-filter) cigarettes smoking and with SRIH. Nicotine significantly increased serum GH levels about 3.5 fold. Naloxone alone did not change GH rise induced by cigarette smoking. The stimulatory effect of GH by nicotine was completely blocked by SRIH. In the presence of both SRIH and naloxone, GH levels rose 1.5 fold in response to nicotine. Since naloxone only partially reversed the inhibiting action of SRIH, only a partial involvement of opioid peptides in SRIH action might be supposed. Alternatively, SRIH and naloxone-sensitive opiates might produce this inhibiting effect on GH rise in response to cigarette smoking through independent pathways.
authors.affiliation: Department of Internal Medicine and Biomedical Sciences, University of Parma, Via A. Gramsci 14, 43126, Parma, Italy. vittorio.coiro@unipr.it
authors.forename: Vittorio
authors.initials: V
authors.lastname: Coiro
authors.forename: Riccardo
authors.initials: R
authors.lastname: Volpi
authors.forename: Adriano
authors.initials: A
authors.lastname: Stella
authors.forename: Simona
authors.initials: S
authors.lastname: Cataldo
authors.forename: Claudio
authors.initials: C
authors.lastname: Giumelli
authors.forename: Francesco
authors.initials: F
authors.lastname: Maccanelli
authors.forename: Anna
authors.initials: A
authors.lastname: Araldi
authors.forename: Paolo
authors.initials: P
authors.lastname: Chiodera
mesh_terms: D000328:Adult; D019382:Human Growth Hormone / Q000037:antagonists & inhibitors* / Q000097:blood / Q000378:metabolism*; D006801:Humans; D008297:Male; D009270:Naloxone / Q000494:pharmacology*; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D012907:Smoking / Q000097:blood*; D013004:Somatostatin / Q000037:antagonists & inhibitors* / Q000494:pharmacology*; D055815:Young Adult
chemical_list: D019382:Human Growth Hormone; D009270:Naloxone; D013004:Somatostatin