Jacobs M L, Chandrashekar V, Bartke A, Weber R F
Department of Internal Medicine, University of Dijkzigt, Rotterdam, The Netherlands.
Exp Nephrol. 1997 Jul-Aug;5(4):337-44.
The renal growth and hyperfiltration observed in humans and animals with early diabetes might be dependent on growth hormone (GH) and insulin-like growth factor (IGF)-I. The aim of this study was to investigate the early changes in kidney IGF-I in experimental diabetes in mice transgenic for bovine GH and in genetically GH-deficient Ames dwarf mice.
At 2, 4 and 8 days after a single intraperitoneal injection with streptozotocin, animals were weighted, bled and killed; plasma was analyzed for glucose and IGF-I. IGF-I levels were determined in tissue from snap-frozen kidney and liver.
Body weight decreased significantly after the induction of diabetes. Kidney weight increased significantly in GH-transgenic, but not in normal or dwarf mice. Plasma IGF-I was significantly decreased at day 2 in GH-transgenic and normal mice, while liver IGF-I was increased at day 4 in all mice. Kidney IGF-I increased significantly in normal and GH-transgenic mice and was increased more than 3-fold at day 4 in GH-transgenic mice. In dwarf mice, no kidney IGF-I was detectable.
The diabetes-induced increase in renal IGF-I is dependent on the presence of GH. GH deficiency may protect diabetic animals from early changes in the kidney.
在患有早期糖尿病的人类和动物中观察到的肾脏生长和超滤可能依赖于生长激素（GH）和胰岛素样生长因子（IGF）-I。本研究的目的是调查转基因表达牛GH的小鼠和遗传性GH缺乏的艾姆斯侏儒小鼠在实验性糖尿病中肾脏IGF-I的早期变化。
在单次腹腔注射链脲佐菌素后2、4和8天，对动物进行称重、采血并处死；分析血浆中的葡萄糖和IGF-I。测定快速冷冻的肾脏和肝脏组织中的IGF-I水平。
糖尿病诱导后体重显著下降。GH转基因小鼠的肾脏重量显著增加，但正常小鼠和侏儒小鼠未增加。GH转基因小鼠和正常小鼠在第2天时血浆IGF-I显著降低，而所有小鼠在第4天时肝脏IGF-I增加。正常小鼠和GH转基因小鼠的肾脏IGF-I显著增加，GH转基因小鼠在第4天时增加超过3倍。在侏儒小鼠中，未检测到肾脏IGF-I。
糖尿病诱导的肾脏IGF-I增加依赖于GH的存在。GH缺乏可能保护糖尿病动物免受肾脏早期变化的影响。
