Measurement of mitochondrial membrane potential in leukocyte suspension by fluorescent spectroscopy

A method for evaluating mitochondrial membrane potential in isolated leukocyte suspension with the use of sensitive fl uorescent cation-active dye 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolocarbocyanine (JC-1) and spectrophotometry is described. JC-1 monomer rapidly penetrates through mitochondrial membrane of living cell and form aggregations characterized by red fl uorescence (λ = 585 nm). In case of mitochondrial membrane depolarization (early sign of apoptosis), JC-1 is not accumulated in the mitochondria and is present in the cytoplasm as a monomer characterized by green spectral fl uorescence (λ = 510 nm). The method can be used for evaluation of the function of living cells and mechanisms regulating energy metabolism by evaluating the mitochondrial membrane potential.