[Liver mitochondrial respiration during hyperthermia].

The influence of hyperthermia on liver mitochondrial respiration and liver metabolites levels was studied by increasing body temperature to 41.0 degrees C in rats under oxygen and nitrous oxide anesthesia maintaining constant PaCo2. At 41.0 degrees C, the increase in ATP and energy charge level (EC) by Atkinson and the increase of state 3 and RCR in NADH linked substrate were observed. After maintaining body temperature at 41.0 degrees C for 30 minutes, the decrease in ATP, EC, state 3, RCR and ADP/O were observed. The degree of change from 38.0 degrees C to 41.0 degrees C in state 3, state 4, RCR and ADP/O was greater in NADH linked substrate than in non-NADH one. After keeping body temperature at 38.0 degrees C for 30 minutes by the whole body cooling, the recovery of EC, state 3 and RCR was observed. The effects of cooling with drugs (dantrolen or methyl-prednisolone) had no consistent effect. These findings suggest that the hyperthermic stress on mitochondrial respiration is focused on complex I in electron transport system.