STUDIES OF HEPATIC RECEPTORS FOR GLYCOPROTEINS

糖蛋白的细胞定位和糖特异性 确定了大鼠肝窦细胞的识别系统。 识别N-乙酰葡糖胺/甘露糖的肝受体 终止的糖蛋白主要位于内皮细胞上。 这些受体对葡萄糖敏感。禁食会增加 这些受体，而糖尿病则消除了禁食的这种作用。 并损害该受体在体内的功能。这些调查结果表明 糖尿病糖蛋白代谢异常的机制。这 碳水化合物识别系统可能在去除中起重要作用 潜在的自身破坏性糖蛋白溶酶体水解酶和其他 糖蛋白酶从循环正常生理 条件和疾病状态。

The cellular location and carbohydrate specificities of a glycoprotein recognition system on rat hepatic sinusoidal cells have been determined. The hepatic receptors which recognize N-acetylglucosamine/mannose terminated glycoproteins are located predominantly on endothelial cells. These receptors are glucose sensitive. Fasting increases the number of these receptors whereas diabetes mellitus abolishes this effect of fasting and impairs the function of this receptor in vivo. These findings suggest a mechanism for abnormal glycoprotein metabolism in diabetes mellitus. This carbohydrate recognition system may play an important role in the removal of potentially autodestructive glycoprotein lysosomal hydrolases and other glycoprotein enzymes from the circulation under normal physiological conditions and in disease states.