Electron Microscopic Study of Human Cholestasis. ∗

Summary

In both extrahepatic biliary obstruction and intrahepatic cholestasis, alteration of the bile canalicular wall of liver cells and distortion of normally present microvilli can be demonstrated by electron microscopy. The functional defect is localized into membrane of liver cells, the more so since cytoplasm of liver cells does not necessarily show significant alterations. It is assumed that the lesion in extrahepatic biliary obstruction results from increased hydrostatic pressure while it cannot be decided whether in intrahepatic cholestasis it is primary or also secondary to increased pressure. Microvillous changes are not found in chronic idiopathic jaundice and only focally in viral hepatitis with liver cell injury possibly as the result of intrahepatic cholestatic component. In both types of cholestasis, communication between dilated bile canaliculi and perisinusoidal tissue spaces may account by regurgitation for at least part of the jaundice.