肥胖者外周脂肪组织中leptin受体水平的研究

Leptin receptor in peripheral adipose tissues of obese subjects

目的 研究肥胖者外周脂肪组织瘦素 (leptin)受体表达及探讨肥胖发生发展的机制。方法 用放射配基受体结合方法 ,检测 71例受检者 (其中肥胖 32例 ,超重 1 9例 ,正常对照 2 0例 )外周脂肪组织leptin受体密度。结果 随着体重指数 (BMI)的增加 ,肥胖组和超重组leptin受体密度与对照组比较差异有显著性 (P <0 0 1 ) ,肥胖组与超重组比较差异亦有显著性 (P <0 0 1 ) ;而受体与leptin的结合能力 (Kd 值 )差异无显著性 (P >0 0 5)。 3组间Kd 值差异无显著性 ,表明leptin受体与配基的结合能力与BMI无关。从散点分布图看 ,BMI越大其leptin受体密度越小 ,BMI与最大结合量相关 (r=- 0 76 ,P <0 0 1 )。结论 肥胖者外周脂肪组织中leptin受体的表达与BMI密切相关 ,而肥胖者血液中leptin水平升高 ,表明体内存在leptin受体水平下调致leptin耐受 ,继而形成肥胖。

Objective To investigate the relationship between leptin receptor and obesity by studying the leptin receptor density B max and dissociation constantK d in peripheral adipose tissue in subjects with different body weight mass(BMI). Methods Leptin receptor density B max andK d were assayed via radioligand method in 71 cases, including 32 classified as obese, 19 over-weight and 20 normal controls Results With the escalating of BMI, the leptin receptor density significantly decreased in obese and over-weight group compared with that in normal controls (bothP<0 01), and there was also statistical difference between obese and over-weight group (P<0 01). TheK d values were of no differences among all three groups suggesting no correlation between the binding ability of leptin to its receptor and BMI A negative correlation between BMI and B max(r=-0 76,P<0 01) displayed after all Conclusion Leptin receptor density correlates with the BMI in obese cases and it suggests that the down-regulation of leptin receptor may contribute to the occurrence of leptin resistance and obesity afterwards.