查看文章

We have examined the mechanisms underlying reduced circulating GH concentrations in the obese human. Computer-assisted (deconvolution) analysis was used to determine endogenous GH secretory and clearance rates quantitatively from entire 24-h plasma GH concentration profiles. These analyses revealed that the half-life (t_1/2) of endogenous GH was significantly shorter in obese (11.7 ± 1.6 min) than in normal weight subjects (15.5 ± 0.81 min; P < 0.01). The accelerated blood disposal rate of GH was not due to decreased circulating concentrations of GH-binding protein, since the latter were similar in obese (25 ± 1.0%) and normal weight (24 ± 2.3%) men. However, obese men had significantly fewer GH secretory bursts (3.2 ± 0.53 vs. 9.7 ± 0.67/day; P < 0.01). Among the rare GH secretory bursts that occurred in obese subjects, there were significantly prolonged mean intersecretory burst intervals (282 ± …