Wakita S, Shimizu K, Suzuki K, Nakagawa Y, Yamamoto S, Yamamuro T
Department of Orthopaedic Surgery, Faculty of Medicine, Kyoto University, Japan.
Spine (Phila Pa 1976). 1993 Jan;18(1):159-64. doi: 10.1097/00007632-199301000-00022.
Calpain I is a calcium-dependent cysteine proteinase that has been recently shown to degrade proteoglycan in vitro. The authors injected calpain I, which was purified from human red blood cells, into the intervertebral discs of rabbits. Roentgenograms showed disc space narrowing 1 week after the injection. Histologically, proteoglycan of the nucleus pulposus and anulus fibrosus decreased and notochordal cells in the nucleus pulposus almost disappeared. Biochemical data of the nucleus pulposus showed that the amounts of smaller proteoglycans increased 1 and 4 weeks after the injection. Eight weeks after the injection, histologic and biochemical data showed recovery compared with the data 1 week after injection. These findings show that calpain I is as potent an enzyme as chondroitinase ABC and has milder chemonucleolytic action than chymopapain. Regarding its possible clinical application, autogenous calpain I as purified from the patient's own red blood cells may have advantages over chymopapain and chondroitinase ABC in that it will prevent anaphylactic reaction.
钙蛋白酶I是一种钙依赖性半胱氨酸蛋白酶，最近研究表明其在体外可降解蛋白聚糖。作者将从人红细胞中纯化得到的钙蛋白酶I注射到兔的椎间盘内。X线片显示注射后1周椎间盘间隙变窄。组织学检查发现，髓核和纤维环中的蛋白聚糖减少，髓核中的脊索细胞几乎消失。髓核的生化数据显示，注射后1周和4周较小的蛋白聚糖数量增加。注射8周后，组织学和生化数据显示与注射后1周的数据相比有所恢复。这些发现表明，钙蛋白酶I与软骨素酶ABC一样是一种强效酶，且与木瓜凝乳蛋白酶相比具有更温和的化学髓核溶解作用。关于其可能的临床应用，从患者自身红细胞中纯化得到的自体钙蛋白酶I可能比木瓜凝乳蛋白酶和软骨素酶ABC更具优势，因为它可预防过敏反应。
