FIG. 2.

Separation of mitochondria and plasma membrane of spleen and liver cells. Cells were fractionated, and individual fractions were tested for activity of marker enzymes for mitochondria (SR; ■) and plasma membrane APD; ○). Fractions containing highest levels of each enzyme (arrows labeled M for mitochondria and PM for plasma membrane) were combined and used as the final mitochondrial and plasma membrane fractions in Western blot experiments. Profiles are typical of those obtained in all experiments.