[Changes of mitochondria membrane potential of the uterine smooth muscle under Mg2+ and Ca2+ influence].

Using the method of flow cytometry and potential-sensitive fluorescent dye TMRM the effect of divalent cations on the membrane potential of isolated myometrium mitochondria was studied. It was shown, that Mg2+ (7 mM) addition to the incubation medium induced mitochondrial membrane hyperpolarization. In the case of protonophore CCCP (1 microM) preliminary presence in the incubation medium, Mg2+ addition did not lead to membrane potential hyperpolarization. Addition of Ca24+ leads to membrane potential dissipation. Ca2+ -induced mitochondrial depolarization is the same as NaN3 (10 mM)-induced depolarization. It also was shown that Mg2+ (7 mM) preliminary presence in the incubation medium did not protect mitochondria from Ca2+ -induced depolarization.