Lactic dehydrogenase activity in degenerative neoplastic glial cells after actinomycin application in vitro

Glial tumors of glioblastoma type, cultured in vitro, have been exposed between the 7th and 14th day of growth to actinomycin C and K in a concentration of 5 x 10(-6) M. The developing degenerative changes in the neoplastic cells were observed after 6, 8, 12 and 24 hours after the addition of actinomycin to the culture of the tumor. It has been found, that the developing degenerative changes in the tumor cells are paralleled by a growing activity of the enzyme tested. The degenerative changes were described in the neoplastic cells, beginning from the accumulation of the enzyme activity in small granules of the cell processes up to very high activity of the enzyme in fragments of the breaking down cells. It is suggested that LDH activity is a good marker of cell form degenerative changes.