Electron microscopic study on hepatic fibrosis

Summary

Fine structural changes in the space of Disse were of similar character in hepatitis and cirrhosis.

In early stage of hepatitis, space of Disse was widened, sinusoidal lining was destructed and hemorrhage occurred in space of Disse. Microvilli of hepatic cells were shortened and decreased in number.

In more chronic stage of hepatitis, sinusoidal lining became thicker more than one cell breadth. In the liver of cirrhosis, basement membrane-like structure was seen beneath the sinusoidal lining. Collagen fibrils, which were scarce in normal, increased in space of Disse and extended into the space between hepatocytes. As pericellular fibrosis progressed, these hepatocytes were isolated each other and degenerated.

These alterations of the space of Disse which could be called “Sinusoidal-hepatocellular block,” would impaire exchange between blood stream and hepatocytes, and facilitate degeneration of hepatocytes and the development of fibrosis, and would make hepatic disease chronic.

Two types of fibrils were distinguished in the space of Disse, one striated collagen fibrils 500 A in width and the other more slender non-striated fibrils, which are considered as the immature form of collagen fibrils.