Objective: The aim of the present work was the detection of Mitochondrial dysfunction of Huntington's disease (HD).
Methods: We investigated muscle and muscle mitochondria of 14- to 16-week-old R6/2 mice in comparison with wild-type mice.
Results: Atrophic fibers, increased fuchsinophilic aggregates, and reduced cytochrome c oxidase (15%) were found in HD muscle. With swelling measurements and Ca2+ accumulation experiments, a decreased stability of HD mitochondria against Ca2+-induced permeability transition was detected. Complex I-dependent respiration of HD mitochondria was more sensitive to inhibition by adding 10 microm Ca2+ than wild-type mitochondria.
Interpretation: Data suggest that the decreased stability of HD mitochondria against Ca2+ contributes to energetic depression and cell atrophy.