Seneviratne C, Luo J M, Murphy L J
Department of Internal Medicine, University of Manitoba, Winnipeg, Canada.
Mol Endocrinol. 1990 Aug;4(8):1199-204. doi: 10.1210/mend-4-8-1199.
The low mol wt insulin-like growth factor-binding protein (IGFBP-1) originally isolated from amniotic fluid has been considered to be GH independent. In this report we have examined the effect of GH on hepatic IGFBP-1 expression in the hypophysectomized rat. Using a rat IGFBP-1 cDNA probe we now demonstrated that hepatic IGFBP-1 expression is up-regulated in the GH-deficient rat. In addition, using ligand blotting, an increase in the abundance of a 30-kDa [125I]IGF-I-BP was detected in both hepatic extracts and serum from hypophysectomized rats. After a single ip injection of GH, the IGFBP-1 transcription rate was reduced within 30 min to the levels seen in the sham-operated control rats. Similarly, hepatic IGFBP-1 mRNA abundance was reduced after both acute GH injection and chronic GH treatment for 8 days. These data demonstrate that IGFBP-1 expression is inversely regulated by GH.
最初从羊水分离出的低分子量胰岛素样生长因子结合蛋白（IGFBP-1）被认为不依赖生长激素（GH）。在本报告中，我们研究了GH对垂体切除大鼠肝脏IGFBP-1表达的影响。使用大鼠IGFBP-1 cDNA探针，我们现在证明GH缺乏大鼠肝脏IGFBP-1表达上调。此外，使用配体印迹法，在垂体切除大鼠的肝脏提取物和血清中均检测到30 kDa [125I]IGF-I-BP丰度增加。单次腹腔注射GH后，IGFBP-1转录率在30分钟内降至假手术对照大鼠的水平。同样，急性注射GH和连续8天慢性GH治疗后，肝脏IGFBP-1 mRNA丰度均降低。这些数据表明IGFBP-1表达受GH反向调节。
