Matuliavichius V A, Vareĭkis E I, Lashas L V
Biokhimiia. 1986 Feb;51(2):278-84.
Human erythrocyte lysate was fractionated on various gel filtration media and immunoreactive insulin, insulinase and the influence of individual fractions of the insulin-degrading activity were determined. The hemolysate was shown to contain a complex of substances including an insulin-like substance, insulinase, protease inhibitor and insulinase activator. The insulin-like substance eluted from a Sephadex G-50 column in the same manner as native insulin, and its concentration exceeded the plasma level. Insulinase (Mr 100,000) degraded insulin to the trichloroacetic acid soluble fragments but did not degrade protein or glycoprotein hormones from human pituitaries. Insulinase was inhibited by low temperature, aprotinin and by a newly discovered protease inhibitor from erythrocytes which also inhibits serine proteases--trypsin and chymotrypsin. Another newly discovered substance eluted from a Sephadex G-100 column in the region of low molecular weight substances and showed an insulinase activating activity. The elution patterns of the protease inhibitor and insulinase activator suggest the possibility of the presence of more than one inhibiting and activating factor. The experimental results suggest that the insulin-degrading complex plays a role of a regulator of plasma insulin level. The nonpancreatic origin of the insulin-like substance is also possible.
将人红细胞裂解物在各种凝胶过滤介质上进行分级分离，并测定免疫反应性胰岛素、胰岛素酶以及胰岛素降解活性各组分的影响。结果表明，溶血产物含有包括胰岛素样物质、胰岛素酶、蛋白酶抑制剂和胰岛素酶激活剂在内的多种物质复合物。从Sephadex G - 50柱上洗脱下来的胰岛素样物质，其洗脱方式与天然胰岛素相同，且其浓度超过血浆水平。胰岛素酶（分子量100,000）将胰岛素降解为三氯乙酸可溶性片段，但不降解人垂体中的蛋白质或糖蛋白激素。胰岛素酶受低温、抑肽酶以及一种新发现的来自红细胞的蛋白酶抑制剂抑制，该抑制剂也抑制丝氨酸蛋白酶——胰蛋白酶和糜蛋白酶。另一种新发现的物质在Sephadex G - 100柱上低分子量物质区域洗脱，并表现出胰岛素酶激活活性。蛋白酶抑制剂和胰岛素酶激活剂的洗脱模式表明可能存在不止一种抑制和激活因子。实验结果表明，胰岛素降解复合物在调节血浆胰岛素水平方面发挥作用。胰岛素样物质也可能起源于非胰腺。
