Zhou X, De Schepper J, Vergeylen A, Luis O, Delhase M, Hooghe-Peters E L
Department of Pharmacology, Faculty of Medicine, Free University of Brussels, Belgium.
J Endocrinol Invest. 1997 May;20(5):264-9. doi: 10.1007/BF03350298.
In human obesity, spontaneous and GRF stimulated growth hormone secretion have been shown to be blunted. We used cafeteria diet fed obese rats as a model to study the central mechanisms involved in growth hormone secretion changes which are observed in obesity. We analysed somatostatin messenger RNA and protein levels in the hypothalamic periventricular nucleus of the rats by non radioactive in situ hybridization and immunocytochemistry respectively. The optical density of somatostatin mRNA, measured by a computerized image system, was significantly higher in cafeteria diet fed rats (1014 +/- 87 vs 444 +/- 45; p < 0.05). The integrated optical density of somatostatin protein was also significantly higher in cafeteria rats compared to the control rats (222 +/- 36 vs 114 +/- 24; p < 0.05). In conclusion, cafeteria diet induced obese rats have a higher somatostatin biosynthesis in the periventricular nucleus. Further studies are needed to establish the possible link of this increased somatostatin gene expression with the decreased GH production.
在人类肥胖症中，已证明自发性生长激素分泌以及生长激素释放因子刺激的生长激素分泌均受到抑制。我们将食用自助餐饮食的肥胖大鼠作为模型，来研究肥胖症中所观察到的生长激素分泌变化涉及的中枢机制。我们分别通过非放射性原位杂交和免疫细胞化学方法，分析了大鼠下丘脑室周核中生长抑素信使核糖核酸（mRNA）和蛋白质水平。通过计算机图像系统测量，食用自助餐饮食的大鼠中生长抑素mRNA的光密度显著更高（1014±87对444±45；p<0.05）。与对照大鼠相比，食用自助餐饮食的大鼠中生长抑素蛋白的积分光密度也显著更高（222±36对114±24；p<0.05）。总之，食用自助餐饮食诱导的肥胖大鼠在室周核中有更高的生长抑素生物合成。需要进一步研究来确定这种生长抑素基因表达增加与生长激素分泌减少之间可能存在的联系。
