Leucocyte energy metabolism. VII. Respiratory chain enzymes, oxygen consumption and oxidative phosphorylation of mitochondria isolated from leucocytes.

A new method for the destruction of cell membrane with heparin and for the subsequent isolation of mitochondria from different types of leucocytes (polymorphonuclear leucocytes (PMN) and lymphocytes of human blood, PMN and macrophages of guinea pig peritoneal exudates) is presented. This method is less traumatic to the mitochondria than the usual mechanical procedures. The activites of several enzymes of the respiratory chain were estimated. Oxygen consumption was measured with oxyhaemoglobin as oxygen donor and reaction rate indicator. The integrity of the mitochodria can be demonstrated by the determination of the acceptor control index; the existence of a coupled phosphorylation of ADP to the respiration is clearly demonstrated in all type of cells studied; the ADP/O ratios with several substrates, near to the theoretical values, could be estimated in mitochondria preparation of lymphocytes (normal and leukaemic) and of macrophages. The highest oxidative ratios were found in leukaemic cells.