Collatos C, Barton M H, Schleef R, Prasse K W, Moore J N
Department of Large Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens 30602.
Equine Vet J. 1994 Nov;26(6):474-81. doi: 10.1111/j.2042-3306.1994.tb04053.x.
Much of the pathophysiology associated with equine gastrointestinal diseases is attributed to the effects of endotoxin on haemostasis. Because little is known about the responses of the equine fibrinolytic system to endotoxin, regulation of the system was investigated. Tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor type-1 (PAI-1) were identified as the primary plasminogen activator and plasminogen activator inhibitor, respectively, in equine blood. Under experimental conditions, the equine fibrinolytic system responded to endotoxin in a manner similar to that reported in man, with an early, transient increase in t-PA activity followed by an overwhelming and prolonged increase in activity of PAI-1. To investigate the response of the equine fibrinolytic system to clinical endotoxaemia, endotoxin concentrations were measured in plasma and peritoneal fluid, and activities of t-PA and PAI-1 were compared between healthy horses (n = 38) and horses with naturally occurring gastrointestinal diseases (n = 150). It was observed that plasma PAI-1 and peritoneal t-PA were increased concurrently in abnormal horses; and that these increases were associated with the presence of endotoxin. The results of this study suggest that 1) fibrinolysis is regulated in horses in a manner similar to that in man; 2) regulation of fibrinolysis is altered in endotoxaemic horses with gastrointestinal diseases; 3) events occurring in the vascular system may not reflect those in the peritoneal cavity; and 4) t-PA activity is increased in the peritoneal fluid of endotoxaemic horses with gastrointestinal diseases.
许多与马胃肠道疾病相关的病理生理学都归因于内毒素对止血的影响。由于对马纤维蛋白溶解系统对内毒素的反应了解甚少，因此对该系统的调节进行了研究。组织型纤溶酶原激活物（t-PA）和纤溶酶原激活物抑制剂-1（PAI-1）分别被确定为马血液中的主要纤溶酶原激活物和纤溶酶原激活物抑制剂。在实验条件下，马纤维蛋白溶解系统对内毒素的反应方式与人类报道的相似，t-PA活性早期短暂升高，随后PAI-1活性压倒性且持续升高。为了研究马纤维蛋白溶解系统对临床内毒素血症的反应，测量了血浆和腹腔液中的内毒素浓度，并比较了健康马（n = 38）和患有自然发生的胃肠道疾病的马（n = 150）的t-PA和PAI-1活性。观察到异常马匹的血浆PAI-1和腹腔t-PA同时升高；并且这些升高与内毒素的存在有关。本研究结果表明：1）马的纤维蛋白溶解调节方式与人类相似；2）患有胃肠道疾病的内毒素血症马的纤维蛋白溶解调节发生改变；3）血管系统中发生的事件可能无法反映腹腔中的事件；4）患有胃肠道疾病的内毒素血症马的腹腔液中t-PA活性升高。
