豚鼠黄疸出血型钩端螺旋体病肝微胆管及紧密连接的电镜研究

作者用冷冻复型及扫描电镜研究了钩体病黄疸豚鼠模型的肝脏。黄疸发生时,大量钩端螺旋体粘附于肝细胞血窦面、穿行肝细胞内或之间,甚至进入微胆管。肝细胞紧密连接的条索断裂,数量减少以至消失。微胆管内微绒毛减少,变形,管腔扩大,分支明显,并与Disse间隙沟通。肝间隙连接及其他膜性结构未见明显改变。

A STUDY OF FREEZE REPLICA AND SEM ON THE HEPATOCYTIC TIGHT JUNCTIONS AND CANALICULI IN GUINEA PIG WITH LEPTOSPIROSIS ICTEROHAEMORRHAGIAE

The fine structure changes of the tightjunctions and canaliculi of hepatocytes inleptospirosis icterohaemorrhagiae model ofguinea pig were examined by the freezereplica and scanning electron microscopy(SEM) of tissue fracture face. The functionalstate of liver in examined guinea pig wasdetermined as well. On the fourth day of hypodermic inoc-ulation with Leptospira icterohaemorrhagiae(strain 017 of serovar Lai), 12 out of 20infected animal appeared jaundice. Theirserum index of jaundice were significantlyelevated (P<0.001). Most of the serum vanden Bergh's test were directly immediatereaction. The serum GPT and GOT activ-ity had no significant difference comparedto those in control (P>0.05). When jaun-dice appeared, there were considerable mor-phologic alterations in the bile canaliculiand tight junctions, such as, decrease innumber or even complete absence of thetight junctional strands; disruption of thestrand into small fragments; discontinuityand albuminal stretching of local strands.Various sized vacuoles which might be thebile product were no only often found inthe canaliculi with enlarged lumen but alsoin space of Disse. In space of Disse therewere a lot of leptospires attached closely tothe membrane of hepatocyte or penetratedthrough interhepatocytic surface into bilecanaliculi with side branches, some of thelatter were seen communicated with thespace of Disse. Similar changes had notbeen found in leptospirosis animal withoutjaundice. Either the altered tight junction orthe free communication between the sidebranches of canaliculi and space of Dissecould allow regurgitation of the bile productinto blood, that might play an importantrole in the pathogenesis of jaundice inleptospirosis.