肥胖大鼠形成过程中血清瘦素、血浆Ghrelin及下丘脑神经肽Y水平的变化

The changes of lepin,ghrelin and NPY in the obesity development of rats

目的观察在食源性肥胖(DIO)大鼠模型形成过程中,血清瘦素(Leptin)、血浆Ghrelin及下丘脑神经肽Y(NPY)的变化。方法取模型形成过程中2个时间点,分为正常对照(NC)组、DIO4周组(高脂饮食喂养4周)和DIO 8周组(高脂饮食喂养8周)。测量血清Leptin、血浆Ghrelin水平及下丘脑NPY浓度和mRNA的表达。结果在DIO大鼠模型形成过程中,DIO 4周和DIO 8周组空腹血清Leptin浓度明显高于NC组[(0.34±0.05),(0.49±0.03)vs(0.24±0.03)ng/ml](P<0.05);空腹血浆Ghrelin浓度明显低于NC组[(1.84±0.21),(1.62±0.23)vs(2.01±0.20)ng/ml](P<0.05);下丘脑NPY浓度及mRNA表达均明显高于NC组[NPY浓度:(162.8±20.1),(196.2±19.9)vs(134.3±17.2)pg/ml;NPY mRNA:(1.16±0.13),(1.55±0.16)vs(0.87±0.16)](P均<0.05)。下丘脑NPY浓度及mRNA表达与血清Leptin浓度呈正相关(r分别为0.950、0.914,P<0.05),与血浆Ghrelin浓度呈负相关(r分别为-0.889、-0.908,P<0.05)。结论随着DIO大鼠肥胖动物模型的形成,下丘脑NPY表达逐渐增强,与空腹血清Leptin浓度正相关,与空腹血浆Ghrelin浓度负相关。

Objective The purpose of our research is to observe the changes of lepin, ghrelin and hypothalamic neuropeptide Y（NPY） in the development of diet-induced obesity （DIO） rats. Methods Choosing two time points in the development, the rats was devided into three groups, the control group, DIO 4W group （high fat diet for 4 weeks） and DIO 8W group （high fat diet for 8 weeks）. The fasting serum levels of lepin, plasma levels of ghrelin, hypothalamic NPY oncentrations and NPY mRNA expressions were measured. Results During the development of DIO rats, the fasting serum levels of iepin showed an increased,and the DIO 4W and DIO 8W groups were significantly higher than in control group[- （0.34 ± 0. 05 ）, （0.49 ± 0.03 ） vs （0.24 ± 0. 03） ng/ml, P 〈 0.05 ] ; The fasting plasma levels of ghrelin were decreased,and the DIO 4W and DIO 8W groups were lower than in control group[（1.84± 0.20）, （1.62± 0.23） vs （2.01 ±0. 20） ng/ml, P〈 0.05 ] ; Hypothalamic NPY concentrations and NPY mRNA expression levels in DIO 4W and DIO 8W groups were significantly higher than in control group [NPY concentration： （162.8±20.1）, （ 196.2 ±35.9） vs （ 134.3 ±17.2） pg/mh P〈 0.05 ; NPY mRNA expression level： （1.16± 0. 13）, （ 1.55 ± 0. 16） vs （0.87 ± 0.16） pg/ml, P〈0. 05]. Hypothalamic NPY concentrations（pg/ml） and NPY mRNA expression levels were positively correlated with the serum leptin levels （r=0. 950 and r=0. 914,P〈0.05） and negatively correlated with plasma ghrelin levels（r=--0. 889and r=- 0. 908, P（0. 05）. Conclusion In the development of DIO rats, the hypothalamic NPY concentrations and NPY mRNA expression levels increased gradually, which are positively correlated to the serum leptin levels and negatively correlated to the plasma ghrelin levels.