Abstract
1. In the present experiment, Parathion (diethyl-paranitrophenyl-thiophosphate) was administered subcutaneously in a varying dose of 2, 4, 8, 12 and 16 mg/kg twice per . week on adult rats and histopathological investigations were made on the liver of each animal.
2. Vacuolar degeneration and various other retrogressive and tissue traumatic changes of hepatic cells observed in the present experiment are considered as the lesions formed by the tissue intoxication due to the hypoxydosis caused by the administration Parathion.
3. Changes of hepatic cells which advance from the tissue traumatic changes, namely, colliquative changes to the circumscribed necrosis are considered to be non-reversible.
4. Glisson's sheath and the interlobular connective tissues were seen to have undergone hydromatous expansion clearly demonstrating each lobular construction and the oppression, atrophy, destruction etc of hepatic cells were recognized on the part where lobules contact each other. In view of the changes listed above, healing processes are considered to follow fibrous consolidation together with hydromatous consolidation.
5. Colliquative degeneration is considered as a prodromal phenomenon of localized necrosis. At the stage of colliquative degeneration, however, it is difficult to demonstrate the movement of the distribution of fat morphologically. Fat is considered to appear when there occur considerable changes in the construction of hepatic tissues by the advancement of colliquative changes.
