甲状腺功能亢进症患者血浆Ghrelin水平的改变及其影响因素探讨

Changes of plasma ghrelin levels and relevant factors in hyperthyroidism patients

目的了解甲状腺功能亢进症患者血浆生长激素促分泌素受体的内源性配体Ghrelin水平的改变及抗甲状腺药物治疗对血浆Ghrelin水平的影响。方法采用酶联免疫法测定正常成人和初发甲亢患者治疗前后血浆Ghrelin水平,分析血浆Ghrelin与FT3、FT4、S-TSH、体质量指数、体脂百分比、空腹血糖的关系。结果甲亢患者血浆Ghrelin水平较对照组明显降低[分别为(468±136)、(751±212)ng/L,P<0.01]。经他巴唑治疗1个月后血浆Ghrelin水平、体质量及BMI升高(P<0.01),他巴唑治疗2个月后血浆Ghrelin水平与正常对照组比较无明显差异[分别为(670±214)、(751±212)ng/L,P>0.05]。相关性分析表明血浆Ghrelin水平与FT4、FT3浓度呈明显负相关(r=-0.43,r=-0.37,P<0.01),而与S-TSH和体脂百分比呈明显正相关(r=0.29,P<0.01;r=0.26,P<0.05)。多元线性逐步回归分析提示FT4是影响血浆Ghrelin水平的独立相关因素。结论甲亢患者血浆Ghrelin水平的显著降低可能与甲亢患者高水平的甲状腺激素抑制了Ghrelin的分泌有关。

Objective To investigate plasma ghrelin levels in the patients with hyperthyroidism and their relation to thyroid hormones. Methods Plasma ghrelin levels were assayed by ELISA in 20 normal subjects and 26 hyperthyroidism patients before and after medical treatment. The relationship between plasma ghrelin levels and thyroid hormones was also analyzed. Results Plasma ghrelin levels were significantly lower in the hyperthyroidism patients than the controls [ （468 ± 136） ng/L vs （751 ±212） ng/L, P 〈0.01 ]. After Methimazole treatment for 1 month, plasma ghrelin levels, body weight and Body Mass Index （BMI） were significantly increased in hyperthyroidism patients in comparison with the controls [ （468 ± 136） ng/L vs （563 ± 194） rig/L, （51.1 ±8.3） kgvs （54.2 ±8.1） kg, （19.8 ±2.4） kg/m^2 vs （20.6 ±2.2） kg,/m^2, P〈0.01]. Two months later, plasma ghrelin levels in patients treated with Methimazole were similar to the controls I （670 ± 214） ng/L vs （751 ±212） ng/L, P 〉0.05 ]. Plasma ghrelin levels were correlated negatively with FT4 and FT3 （r= -0.43, and r = -0.37, both P〈0.01）, and positively with S-TSH and FAT% （r=0.29, P 〈0.01 ; r =0.26, P 〈0.05 ）. Multiple regression analysis showed that FT4 was independent factor related to plasma Ghrelin levels. Conclusion The circulating levels of plasma ghrelin are reduced in the patients with hyperthyroidism, but they recover after treatment. The ghrelin secretion may be suppressed by increasing thyroid hormones.