瘦素在男性青春期发育中的作用

Role of leptin in development of peripubertal boys

目的 探讨瘦素在男性青春期发育中的作用及其与胰岛素、生长激素、睾酮和雌二醇的相互关系。方法 筛选 7～ 17岁单纯性肥胖男生 15 0人 ,以相互身高相差不超过 2cm ,年龄相差不超过 3个月进行配比 ,选择正常组和营养不良组各 15 0人。结果 肥胖组血清瘦素水平显著高于正常组 ,正常组显著高于营养不良组。不论组别 ,男生血清瘦素水平均随年龄增长先升高再下降 ,肥胖组峰值为 16 96 μg/L(10～ 11岁 ) ,正常组和营养不良组分别为 10 2 5 μg/L和 5 0 8μg/L(11～ 12岁 )。男生血清瘦素水平从TannerG1期到G2 期显著上升 ,之后G2 4期出现逐步下降 ,G5期再次升高。 7～17岁血清胰岛素水平随年龄增长而升高 ,生长激素、睾酮和雌二醇水平于 10～ 11岁开始随年龄增长而升高。瘦素与胰岛素呈正相关 ,与生长激素呈负相关 ,与睾酮呈强负相关 ,与雌二醇无相关性。结论 瘦素可能有加速男性青春期发育的作用 ,而在启动和维持男性青春期发育中是非决定性因素。G5期瘦素水平再次增长具有抑制生长激素分泌作用 ,预示青春期发育结束。

Objectives To study the role of leptin in the development boys during their puberty and its relationship with insulin (INS),growth hormone (GH),estradiol (E 2) and testosterone (T). Methods One hundred and fifty boys with simple obese aged 7 to 17 years,150 normal healthy boys and 150 boys with malnutrition matched for age (±3 months) and height (±2 cm) were selected. Serum levels of leptin,INS,GH,E 2 and T were measured for them. Results Serum level of leptin in obese group was significantly higher than that in mormal group,and that in normal group was sigificantly higher than that in malnourished group. In the all three groups,serum level of leptin increased with age first until peak value,then began to decrease,with peak value of 6.96 μg/L at ages of 10—11 y in obese group,10.25 μg/L at ages of 11—12 y in normal group and 5.08 μg/L at ages of 11—12 y in malnourished group. Serum level of leptin increased steadily from Tanner stages G 1 to G 2,then began to decrease steadily in G 2 to G 4. Serum level of leptin increased again in stage G 5. Serum level of INS in boys increased steadily with age from 7 to 17 years old. Serum levels of GH,T and E 2 in boys began to increase since 10—11 years old. Serum level of leptin positively correlated with serum level of INS and negatively correlated with serum levels of GH and T,but not correlated with serum level of E 2. Conclusions Leptin may promote pubertal development of boys,but not the determinant factor in triggering and maintaining their pubertal development. Re-increase in level of leptin during stage G 5 could inhibit secretion of GH,and signalize the end of puberty in boys.