FIG. 4.

Effect of TNF-α on mitochondria in control, RIP, and FADD knock out cells. Cells (control, RIP, and FADD knock out cells) were treated with TNF-α (1 nM) for indicated time intervals. The number of cells with mitochondrial damage in early phase (A) and late phase (B) was determined by scoring 250 cells from 30 different microscopic fields in the electron microscope. The diagram shows the number of pathologically altered cells. Columns, mean from three different experiments; bars, SD. *p < 0.05; **p < 0.01, Student's t test.