Mechanical ventilation preserves diaphragm mitochondrial function in a rat sepsis model

Intensive Care Medicine Experimental

Table 2 Mitochondrial oxygen consumption and ATP synthesis

	Control	Sepsis	MV-control	MV-sepsis
State 3 respiration (natm/min/mg)	42±3	25±3*^†₤	40±2	34±4
State 4 respiration (natm/min/mg)	12.8±3.9	6.2±1.1	11.1±1.5	8.8±2.4
RCR	4.18±0.81	4.32±0.53	3.83±0.55	4.04±0.72
ATP production	119±21	53±15*^†₤	130±23	95±10
ATP/O	2.75±0.50	2.20±0.60	3.23±0.62	2.86±0.41

Measures were performed on diaphragm mitochondria from rats of the four following groups: spontaneously breathing controls (Control), spontaneously breathing sepsis group (Sepsis), mechanically ventilated control group (MV-control) and a mechanically ventilated sepsis group (MV-sepsis). Mitochondria were energized with succinate as respiratory substrate in the presence of rotenone State 3 phosphorylating respiration as well as ATP production were measured at 100 µM of exogenous ADP. State 4 respiration was obtained by inhibiting the ATP synthase with 3 µg/ml of oligomycin. Data are means ± SEM from 6 animals per group. *p < 0.05 sepsis versus Control; ^†p < 0.05 sepsis versus MV-control; ^£p < 0.05 sepsis versus MV-sepsis