Electron microscopic study on the ascites hepatoma--comparative observations.

Further detailed observation has been made on the ultrastructure of the six strains of Yoshida ascites hepatoma representing various growth rates and pathological characteristics. Common to all the ascites hepatoma were the large, irregular nuclei with hypertrophied nucleoli, increased free ribosomes, and no microbodies. The present investigation throughout many transplant generations has revealed several genetically defined characteristics for each strain. These fine cytological characteristics are as follows: AH-13-clumped and dispersed glycogen granules, fine fibrils, and sparse endoplasmic reticulum; AH-130-well-developed Golgi lamellae, fine fibrils, single cisternae of endoplasmic reticulum, and short tight junction; AH-130R-mitochondria with electron-lucent matrix; AH-272mitochondria with electron-lucent matrix, fine fibrils, and single cisternae of endoplasmic reticulum; AH-601-small, round or oval mitochondria, relatively increased number of dilated cisternae of rough-surfaced endoplasmic reticulum, short tight junction, and increased site of intermediate junction; AH-7974-small and compact mitochondria, elongated cisternae of rough-surfaced endoplasmic reticulum, occasionally forming parallel array, typical junctional complex-tight, intermediate, and macula adhaerens (desmosome) which is described in detail in this paper, and vesicles containing dense amorphous materials along the intercellular canaliculi. The fine cytological characteristics of each strain were discussed with their pathological properties.