Ip T P, Hoffman D M, O'Sullivan A J, Leung K C, Ho K K
Garvan Institute of Medical Research, St. Vincent's Hospital, Sydney, New South Wales, Australia.
J Clin Endocrinol Metab. 1995 Apr;80(4):1278-82. doi: 10.1210/jcem.80.4.7714101.
To determine whether adult serum GH-binding protein (GHBP) is regulated by androgen, serum GHBP concentrations were compared between 20 normal and 18 hypogonadal men matched for age and body mass index, and the effect of im testosterone treatment (250 mg testosterone enanthate) on GHBP levels in the 18 hypogonadal men was studied. Nine of the hypogonadal subjects had coexistent GH deficiency. Serum GHBP concentration was measured by a ligand immunofunctional assay. The mean serum GHBP level in untreated hypogonadal men was not significantly different from that of normal men (0.98 +/- 0.15 vs. 1.17 +/- 0.16 nmol/L). The mean serum insulin-like growth factor I (IGF-I) level was significantly lower in the hypogonadal men (132 +/- 22 vs. 206 +/- 17 ng/mL; P < 0.01). Basal testosterone (3.7 +/- 0.7 nmol/L) in hypogonadal men increased during treatment to a mean level of 29.1 +/- 2.8 nmol/L, which was not significantly higher than that in normal men (22.6 +/- 1.9 nmol/L). The mean serum GHBP level in hypogonadal men fell significantly during treatment to 0.60 +/- 0.11 nmol/L (P = 0.0003), whereas the serum IGF-I level rose significantly to 151 +/- 26 ng/mL (P < 0.04). The decrease in GHBP level was significant in both the GH-sufficient and GH-deficient subjects (P < 0.02 in both instances), whereas the increase in IGF-I level was significant in the GH-sufficient group (199 +/- 22 to 235 +/- 29 ng/mL; P < 0.04) but not in the GH-deficient group (53 +/- 7 to 55 +/- 5 ng/mL; P > 0.8). Thus, serum GHBP is normal in hypogonadal men but is reduced by testosterone treatment irrespective of endogenous GH-secretory status. It was concluded that the effect of testosterone on GHBP is pharmacological and occurs independent of GH mediation.
为了确定成年男性血清生长激素结合蛋白（GHBP）是否受雄激素调节，我们比较了20名年龄和体重指数相匹配的正常男性与18名性腺功能减退男性的血清GHBP浓度，并研究了注射睾酮治疗（250mg庚酸睾酮）对18名性腺功能减退男性GHBP水平的影响。18名性腺功能减退受试者中有9人同时存在生长激素缺乏。血清GHBP浓度通过配体免疫功能测定法进行测量。未经治疗的性腺功能减退男性的血清GHBP平均水平与正常男性相比无显著差异（0.98±0.15对1.17±0.16nmol/L）。性腺功能减退男性的血清胰岛素样生长因子I（IGF-I）平均水平显著低于正常男性（132±22对206±17ng/mL；P<0.01）。性腺功能减退男性的基础睾酮水平（3.7±0.7nmol/L）在治疗期间升高至平均水平29.1±2.8nmol/L，这与正常男性（22.6±1.9nmol/L）相比无显著升高。性腺功能减退男性的血清GHBP平均水平在治疗期间显著下降至0.60±0.11nmol/L（P = 0.0003），而血清IGF-I水平显著升高至151±26ng/mL（P<0.04）。GHBP水平的下降在生长激素充足和生长激素缺乏的受试者中均有显著性（两种情况下P均<0.02），而IGF-I水平的升高在生长激素充足组中有显著性（199±22至235±29ng/mL；P<0.04），但在生长激素缺乏组中无显著性（53±7至55±5ng/mL；P>0.8）。因此，性腺功能减退男性的血清GHBP水平正常，但无论内源性生长激素分泌状态如何，睾酮治疗都会使其降低。研究得出结论，睾酮对GHBP的作用是药理学作用，且独立于生长激素介导而发生。
