Figure 3. Ca²⁺-induced increase in respiration is accelerated by 15d-PGJ₂.

(A) Respiration rate of mitochondria (1 mg/ml) in the absence (open bars) or presence (closed bars) of 15d-PGJ₂ (10 μM). The respiration rate is shown in the presence of 5 mM succinate or glutamate (10 mM) and malate (2.5 mM), with or without ADP (10 mM). (B) Representative respiration traces of mitochondria in the presence of succinate (5 mM) and rotenone (1 μM) in which 15d-PGJ₂ (10 μM) was present from the beginning of the incubation and Ca²⁺ (10 μM) was added 2 min after incubation. Traces shown are untreated control, 15d-PGJ₂ alone, Ca²⁺ alone and Ca²⁺ added after the addition of 15d-PGJ₂. (C) Respiration rates measured from traces such as those shown in (B) over the 100 s indicated by the grey box in (B). Results are expressed as the means±S.E.M. for at least three experiments. *, P<0.01; #, P<0.001.