A study of ATP-induced reversal of spontaneous swelling in isolated rat liver mitochondria

The results establish that there is heterogeneity of the mitochondrial population in the isolated suspension in so far as some of the mitochondria are more susceptible to spontaneous swelling than others and that in the swollen suspension, some mitochondria contract under the influence of ATP while others do not. The swelling involves loss of mitochondrial matrix density and cristal organisation, while contraction is accompanied by some degree of cristal reconstitution and recovery of electron dense matrix.