Isolation of mitochondria from ascites tumor cells permeabilized with digitonin.

A new, improved procedure for isolating mitochondria from ascites tumor cells is described. The unique feature of this technique is the use of digitonin to make the cells susceptible to disruption by Teflon pestle/glass vessel homogenization. The yield and respiratory control ratios of mitochondria isolated by this method from murine Ehrlich ascites tumor cells and rat AS30-D ascites hepatoma cells are significantly better than those obtained for mitochondria isolated by the commonly employed Nagarse method, which involves the use of proteolytic enzymes. Moreover, mitochondria isolated by this new procedure from three different lines of tumors exhibit respiratory control ratios with both adenosine diphosphate and a respiratory uncoupler comparable to those obtained with mitochondria present in situ within digitonin-permeabilized tumor cells.