丝氨酸蛋白酶在脑损伤继发病损中的作用

Effects of serine proteases in secondary brain lesion after brain trauma

在中枢神经系统中 ,氧气 ,二氧化碳和一些基本营养物质可以通过血脑屏障 ,而其他血液组分和大分子蛋白则不能通过。卒中、脑创伤等均可破坏血脑屏障完整性 ,使血清白蛋白之类的大分子通过血脑屏障进入脑组织间隙。脑血管病变时 ,中枢神经系统中的血源性丝氨酸蛋白酶 ,如凝血酶、组织纤维蛋白溶酶原激活剂和纤溶酶等的出现很有意义。目前发现丝氨酸蛋白酶类与胶质瘢痕形成、水肿、癫痫发作和神经组织坏死等过程相关。

The protective blood brain barrier normally allows diffusion of small molecules such as oxygen and carbon dioxide, and transport of essential nutrients, but excludes large proteins and other blood constituents from the interstitial space of the CNS. However, head trauma, stroke, status epilepticus and other pathological conditions can compromise the integrity of this barrier, and allow blood proteins as large as albumin to gain access to the extracellular spaces.The appearance of serine proteases such as thrombin, tissue plasminogen activator and plasmin in the CNS have come under increasing scrutiny. Evidence now supports a role serine proteases in the sequence of events that can lead to glial scarring, edema,seizure and neuronal death.