GROWTH HORMONE (GH) THERAPY: EFFECTS ON IN VITRO ADIPOCYTE INSULIN (I) SENSITIVITY ODRREIATE WITH ANTHROPOMETRIC RESPONSE

Abstract

GH therapy is associated with adipose tissue redistribution from an android (abdominal; abd) to a gynecpid (gluteal; glt) pattern. In 6 GH-deficient children we studied the anatomic site-specific effects of GH Rx on adipocyte in vitro response to I ancr adrenergic stimulation, and tneir correlation with anthropometric changes. Adipose tissue samples obtained from abdominal and gluteal sites in fasting subjects by subcutaneous needle aspiration before (Tl) -and after “3 months (T2) of met-hGH (0.1 mg/kg TIW) were incubated for 2 h with 14C-gluoose arid 3H-palmitate plus I (10 or 100 uU/ml), isoproterenol (α-1 adrenergic agonist, 10^-7M) norepinephrine (β-2/α-1 agonist 10^-7M), met-hGH (10 or 100) ng/ml), or dibutyryl cAMP (10^-3M). Rates of lipogenesis and lipolysis were calculated from absolute and relative rates of isotope accumulation after a 2 h incubation. Cell size was determined by osmium fixation. Anthropometry was performed at T1 and T2. There were no consistent differences in response to adrenergic stimulation or to the lipogenic effects of I between T1 and “T2. However, there was a decrease in the antilipolytic effect of I in the abd fat depot following GH Rx which correlated with changes in height, weight, abd cell size, and the abd/glt cell size ratio as summarized: Conclusion: GH Rx desensitizes abd subcutaneous adipocytes to the antilipolytic effects of I. This effect is strongly correlated with gynecoid redistribution of adipose tissue and the growth response. These data increase our understanding of the role of growth hormone in fat accretion. They may also be predictive of growth response to GH Rx.