Kominami E, Hashida S, Katunuma N
Biochim Biophys Acta. 1981 Jun 15;659(2):378-89. doi: 10.1016/0005-2744(81)90064-4.
When leupeptin, a thiol protease inhibitor of microbial origin, was injected into rats, the activity of fructose-1,6-bisphosphate aldolase (D-fructose-1,6-bisphosphate D-glyceraldehyde-3-phosphate-lyase, EC 4.1.2.13) in the liver decreased to about 60% of that in control rats. However, the concentration of aldolase protein in the liver extracts, measured with a specific antibody obtained with enzyme purified on a phosphocellulose column, remained unchanged. Injection of leupeptin also caused a marked increase in the activities of free lysosomal proteases, such as cathepsin B (EC 3.4.22.1), cathepsin L (EC 3.4.22.-), cathepsin D (EC 3.4.23.5) and lysosomal carboxypeptidase A in the cytosol fraction. A clear inverse relationship between aldolase and cathepsin B activities in the cytosol fraction was demonstrated. The possibility that the less active form of aldolase detected in the livers of leupeptin-treated rats was produced during homogenization was excluded by showing that the aldolase activity was not changed by addition of various protease inhibitors to the homogenization medium., When insulin was coinjected with leupeptin, increase in the activity of free cathepsin L and decrease of activity of aldolase produced by the injection of leupeptin was prevented. These findings indicate that modification of aldolase may be due to the action of a lysosomal protease(s). Enhanced sensitivity of lysosomes to osmotic shock was demonstrated in the livers of leupeptin-treated rats, suggesting that the lysosomal membrane is labilized by administration of leupeptin. Incubation of the purified aldolase with the lysosomal fraction produced the same changes in properties of aldolase as those observed in vivo on injection of leupeptin.
当向大鼠注射源自微生物的巯基蛋白酶抑制剂亮抑酶肽时，肝脏中果糖-1,6-二磷酸醛缩酶（D-果糖-1,6-二磷酸 D-甘油醛-3-磷酸裂解酶，EC 4.1.2.13）的活性降至对照大鼠的约 60%。然而，用在磷酸纤维素柱上纯化的酶制备的特异性抗体测定肝脏提取物中醛缩酶蛋白的浓度，其保持不变。注射亮抑酶肽还导致胞质溶胶部分中游离溶酶体蛋白酶（如组织蛋白酶 B（EC 3.4.22.1）、组织蛋白酶 L（EC 3.4.22.-））、组织蛋白酶 D（EC 3.4.23.5）和溶酶体羧肽酶 A 的活性显著增加。在胞质溶胶部分中，醛缩酶与组织蛋白酶 B 的活性之间显示出明显的负相关关系。通过表明向匀浆介质中添加各种蛋白酶抑制剂不会改变醛缩酶活性，排除了在亮抑酶肽处理的大鼠肝脏中检测到的活性较低的醛缩酶形式是在匀浆过程中产生的可能性。当胰岛素与亮抑酶肽共同注射时，可防止因注射亮抑酶肽而导致的游离组织蛋白酶 L 活性增加和醛缩酶活性降低。这些发现表明醛缩酶的修饰可能是由于一种溶酶体蛋白酶的作用。在亮抑酶肽处理的大鼠肝脏中，溶酶体对渗透压休克的敏感性增强，这表明亮抑酶肽的给药使溶酶体膜不稳定。将纯化的醛缩酶与溶酶体部分一起孵育，会使醛缩酶的性质发生与注射亮抑酶肽后在体内观察到的相同变化。
