초록
The isozyme alteration of lactic dehydrogenase in the tissues of albino rat inhaled SO$_{2}$ were studied in vivo and in vitro, with the following results: (1) The H-type of LDH activity relatively dominated in the normal brain, heart and kidney tissues of rat, M-type in the normal lung, liver, and muscle tissues of the animal. (2) When rats inhale SO$_{2}$ in the concentration of 250 ppm, it appears that the M-type tends to predominate in the anaerobic tissues such as liver, kidney and muscle tissues and the H-type in the aerobic tissues such as brain and heart tissues. (3) When 5% SO$_{2}$ is introduced into tissue homogenates, LDH activities in the heart, lung, liver and muscle tissues are increased more than that of introducing room-air only. With sam treatment, LDH activity is decreased in the kidney tissue and no alteration is observed in the brain tissue. (4) Although, after the aeration of SO$_{2}$, the oxygen tension seems to bring decreases in the level of LDH activity in the anerobic tissues such as liver and muscle tissues, while, on the other hand, increases in the level of the activity in the aerobic tissues, such as the brain, heart and lung tissues. (5) Accordinglly, SO$_{2}$ affects LDH activities, its isozyme pattern of each organs, and their metabolic pathway by its absorption of the gas.