Ultrastructural alterations of mitochondria in pre-apoptotic and apoptotic hepatocytes of TNF alpha-treated galactosamine-sensitized mice.

The electron microscopical studies presented here show that characteristic morphological alterations in mitochondria are a very early hallmark of the hepatocellular apoptotic program. Before chromatin condensation occurs, the outer mitochondrial membrane is focally disrupted and the inner membrane protrudes through this gap forming a hernia. The demonstration of cytochrome oxidase in mitochondria revealed a very strong activity in pre-apoptotic and apoptotic cells as well as in apoptotic bodies.