Latent and active plasminogen activator in corneal ulceration.
Latent and active plasminogen activator in corneal ulceration.
复制标题
角膜溃疡中的潜在和活性纤溶酶原激活剂。
DOI：
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发表时间：
1985
影响因子：
4.4
通讯作者：
M. Law
中科院分区：
文献类型：
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作者：
H. M. Wang;M. Berman;M. Law
以往碱烧伤的研究已经证明纤溶酶原激活剂(PA)/纤溶酶系统在角膜溃疡中的重要作用。目前的研究已经利用敏感的、依赖纤溶酶原的荧光分析来证明PA在兔角膜上皮细胞或正常角膜培养物中主要以潜伏（胰蛋白酶或纤溶酶激活）形式（促激活剂）存在。溃疡性角膜的培养在器官培养早期仅显示活性PA，而在培养后期，潜在PA水平增加。因此，溃疡与潜伏到活性PA的明显转化有关。此外，促活化剂和潜伏性胶原酶、活性PA和活性胶原酶在体外的分布相似，表明促活化剂和胶原酶在体外受协调控制。正常上皮细胞和非溃疡性角膜的培养物含有PA分子量分别为72,000和46,000 MW，溃疡性角膜的培养物含有PA分子量分别为72,000、46,000和35,000 MW。双扩散分析表明，兔上皮细胞、成纤维细胞和溃疡角膜产生尿激酶样PA；人角膜提取物和泪液中也含有具有抗uk抗体免疫反应的PA。潜伏形式的PA的存在确定了导致间质溃疡的级联反应的另一个调节水平。
Previous studies of alkali burns have provided evidence for an important role of the plasminogen activator (PA)/plasmin system in corneal ulceration. Current studies have utilized a sensitive, plasminogen-dependent fluorescent assay to demonstrate that PA is present mostly in a latent (trypsin- or plasmin-activatable) form (proactivator) in cultures of rabbit corneal epithelial cells or normal corneas. Cultures of ulcerating corneas demonstrate only active PA early in organ culture, whereas, latent PA levels increase later in culture. Thus, ulceration is correlated with the apparent conversion of latent to active PA. Moreover, profiles of proactivator and latent collagenase and of active PA and active collagenase in vitro, respectively, are similar, suggesting that activator and collagenase are under coordinate control. Cultures of normal epithelial cells and nonulcerating corneas contain PA molecular weight species of 72,000 and 46,000 MW, and ulcer corneas, species of 72,000, 46,000, and 35,000 MW. Double-diffusion analysis indicates that rabbit epithelial cells, fibroblasts, and ulcer corneas produce urokinase (UK)-like PA; and human cornea extracts and tears also contain PA immunoreactive with anti-UK antibodies. The existence of PA in a latent form identifies another level of regulation in the cascades that lead to stromal ulceration.