The ductular cell reaction of rat liver in extrahepatic cholestasis: II. The proliferation of connective tissue

Abstract

Fibrosis is an invariable accompaniment of the ductular cell reaction following ligation of the common bile duct of rats. Inflammatory cells aggregate around the proliferating ductules and may penetrate between their lining cells. Others are found in close apposition to aberrant microvilli of parenchymal liver cells which are in contact with the peri-ductular connective tissue. Only neutrophils undergo necrobiosis and they are phagocytosed by numerous macrophages. The stimulus to fibrogenesis and the cause of the inflammation are unknown. It is suggested that a phlogistic nonlipid material is excreted into ductules and gains access to the connective tissue where its chemotactic effects can be assessed morphologically. The migration of monocytes and their conversion into phagocytic macrophages are thought of as a response to the presence of degenerating neutrophils. Four types of capillary channels are found in the ductular cell reaction: fenestrated and nonfenestrated blood capillaries, lymphatics and stranded parenchymal sinusoids.