Figure 6.

Effects of exogenous membrane on the NO inhibition of mitochondrial respiration. (A) Mitochondria were incubated at 1 mg/ml in state 3 as described in Materials and Methods. NO (1 μM) was added as indicated by the arrow. After inhibition of respiration, liposomes (1 mg of phospholipid per ml) were added as indicated by the arrow, and the resultant NO and O₂ fluxes were monitored. Solid line, control (no liposomes); dashed line, with liposomes. Traces are representative of at least three similar experiments. (B) Inhibition of respiration by NO with and without liposomes was calculated from several experiments of the type shown in A. Data shown are shown in the absence (●) or presence (○) of liposomes.