Sex steroids, GHRH, somatostatin, IGF-I, and IGFBP-1 modulate ghrelin's dose-dependent drive of pulsatile GH secretion in healthy older men.

ABSTRACT:

Context

Ghrelin is a potent endogenous stimulator of GH secretion. However, clinical factors that regulate ghrelin dose-responsiveness are incompletely defined.

Objective

The aim of the study was to test the multipathway hypothesis that testosterone (T) and estradiol, GHRH, and somatostatin (SS) jointly modulate ghrelin's action.

Design/participants/setting

Healthy older men (n = 21) participated in a double-blind, prospectively randomized, placebo (Pl)-controlled study in a Clinical Translational Research Center.

Interventions

To create a range of sex-steroid milieus, men received leuprolide + Pl (n = 10) or leuprolide + T addback (n = 11). Sixteen to 21 d later, subjects received three separate randomly ordered overnight constant i.v. infusions of saline, GHR

SUBMITTER: Veldhuis JD 

PROVIDER: S-EPMC3513533 | biostudies-literature | 2012 Dec

REPOSITORIES: biostudies-literature