SkQ3: The new member of the class of membranotropic uncouplers

In our previous studies we have described the non-equilibrium binding of hydrogen ions to the membranes upon induction of transmembrane proton flux in the model system (BLM) and in mitochondria. In 2009 the investigation program aimed to find uncouplers selectively interacting with the non-equilibrium bound protons was started. This study is devoted to a new representative of this class of uncouplers. The effect of respiratory stimulation evoked by this compound can be suppressed by 50–90% through the elimination of non-equilibrium fraction of protons associated with the outer side of the inner mitochondrial membrane. The peculiarity of this compound results from its belonging to the class of quinones with a high affinity to lipid membranes. It becomes a weak acid (hydroquinone) only after reduction. The formation of hydroquinone in the mitochondria determines the observed effect of respiratory stimulation. Thus, the artificial induction of interaction between redox-reactions and reactions of proton association and dissociation occurring on the surface of the inner mitochondrial membrane was demonstrated for the first time.     

The action of extracellular calcium and the temperature of the isolation of lymphocytes on their viability

The effect of extracellular calcium binding and temperature of isolation and storage of thymus lymphocytes on their viability was studied. The last was evaluated by the fluorescence intensity of fluoresceindiacetate stained cells and by the intracellular ATP content. The rise of temperature of isolation and storage of lymphocytes from 1 degree to 22 degrees C significantly lowered the intracellular ATP concentration in cells storing in dense suspension [(3-4) x 10(9) lymphocytes/ml]. However, the ATP content in lymphocytes increased as a result of short-term incubation by diluted suspension (3 x 10(7) lymphocytes/ml) at 22 degrees C. The fluorescence of fluorescein introduced into lymphocytes decrease in the presence of 1-5 mM EGTA (EDTA).