鸭疫里默氏杆菌感染对鸭血-脑屏障机能的影响

Effects of Riemerella anatipestifer infection on function of duck blood-brain barrier

给10日龄健康鸭颈部皮下接种鸭疫里默氏杆菌(RA)及颈静脉注射明胶酶,分别建立了感染与酶作用的动物模型。以脑脊液中白蛋白含量、血-脑屏障通透性及脑组织学变化等指标研究了感染及酶作用对血-脑屏障机能的影响。结果显示,鸭疫里默氏杆菌感染后第24、48、72、96 h和颈静脉注射明胶酶后第3、6、9、12 h,脑脊液中的白蛋白含量升高,血-脑屏障的通透性增大,基底膜粗糙、部分节段的连续性中断,脑血管周围水肿、管腔面不光滑、内皮细胞肿胀、连接处开放;感染鸭血清中利用明胶酶谱法能检测到鸭疫里默氏杆菌明胶酶。表明,鸭疫里默氏杆菌感染引起鸭血-脑屏障机能障碍,在此过程中明胶酶起着重要作用。

Ten-day-old healthy ducklings were infected with Riemerella anatipestifer（RA） by subcutaneous injection,or with gelatinase by jugular vein and RA infection model and gelatinase treatment model were established, respectively. Based on the mean concentration of albumin in the cerebrospinal fluid （CSF）, permeability of blood-brain barrier（BBB） and pathological changes of cerebral vessels, the dysfunction of the BBB was surmised. In the duck model infected with RA,only the infected duck had higher concentration of albumin in CSF and higher permeability in BBB at hour 24,48,72 and 96 post-infection. There were cerebral vasogenic edema, lumens rough,junction break, basement membrane rough and break at somewhere in brain tissue of infected duck. In the duck model injected with gelatinase from RA, albumin and permeability were higher than those of negative control at hour 3,6,9 and 12. The pathological changes of brain were the same as that of the infected duck. The results showed that blood-brain barrier dysfunction occured in ducks infected with RA and the gelatinase was important to the dysfunction.