Protection of mitochondrial function by mannitol in ischemic acute renal failure.

The effect of isotonic mannitol to provide protection against ischemic renal injury was examined in the dog. Mannitol treatment attenuated the fall in glomerular filtration rate at both 1 and 24 h after the ischemic insult. The functional changes were associated with profound cellular protection, since normal mitochondrial respiration, mitochondrial calcium uptake and release rates were preserved, and excessive mitochondrial calcium accumulation was prevented. These effects at the cellular level appear critical to the protective effect of mannitol after ischemia and are most likely due to prevention of cell swelling.