IN VITRO STUDIES OF L-СARNITINE ACTION ON LYSOSOMAL CYSTEINE PROTEOLYSIS ALONE AND IN OXIDATIVE STRESS

The parameters of the lysosomalcysteine proteinase activity and stability of lysosomal membrane were studied. Isolated lysosomes were incubated in vitro in a solution of L- сarnitine alone, as well as in stimulation of oxidative stress. In vitro incubation in a medium of isolating solution and with addition of oxidant was carried out in the control groups respectively. The activity of cathepsins B, L and H was investigated by spectrofluorimetric method of Barrett &Kirschke in two fractions ? lysosomal and outside of lysosomes. The activity of acid phosphatase used as the main marker of a membrane labilization. It has been found that in vitro action of 5 мМН2О2 60 min does not change the activity of cathepsins B,L and H and stability of lysosomal membrane, wherein L- сarnitinein a concentration of 5 mM at 60 min in vitro incubation causes decrease in the activity of cathepsin H, increase in the activity of cathepsinBwithout affecting the activity of cathepsin L and also causes stabilization of lysosomal membrane both alone and in oxidative stress. Besides it was observed selective permeability of the membrane for cathepsin H after the action of 5 mML-сarnitine.