Fig 1.
Aerobic and anaerobic metabolism of cysteine. H2S formed enzymatically from L- or D-cysteine, in mitochondria is transformed to sulfite which in the reaction catalyzed by SO is oxidized to sulfate (aerobic pathway). Anaerobic metabolism of L-cysteine leads via synthesis of H2S and its further sulfhydration to the formation of sulfane sulfur compounds.
Abbreviations: CBS—cystathionine β-synthase; CSE—γ-cystathionase; CDO—cysteine dioxygenase; SO—sulfite oxidase; TSR—thiosulfate reductase; TST—rhodanese.
Fig 2.
Effects of acute and repeated cocaine (10 mg/kg i.p.) treatment on the levels of ROS (2A, 2B) and lipid peroxidation products (MDA; 2C, 2D) in the rat liver and kidney.
Data are presented as the mean ± SD, n = 8–10/group, **p < 0.01, ***p < 0.001 vs. corresponding control group (Student's t-test).
Fig 3.
Effects of acute and repeated cocaine (10 mg/kg i.p.) treatment on the total-, non-protein- and protein -SH group levels in the rat liver and kidney (A-F).
Data are presented as the mean ± SD, n = 8–10/group, *p < 0.05, **p < 0.01 vs. corresponding control group (Student's t-test).
Fig 4.
Effects of acute and repeated cocaine (10 mg/kg i.p.) treatment on enzymatic activities of γ-GT (A and B) and GST (C and D) in the liver and kidney.
Data were presented as the mean ± SD, n = 8–10/group, *p < 0.05, **p < 0.01, ***p < 0.001 vs. corresponding control group (Student's t-test).
Fig 5.
Effects of acute and repeated cocaine (10 mg/kg i.p.) treatment on the levels of sulfane sulfur (A and B), bound sulfane sulfur (C and D), hydrogen sulfide (E and F) and sulfate (G and H) in the rat liver and kidney.
Data are presented as the mean ± SD, n = 8–10/group, *p < 0.05, **p < 0.01, ***p < 0.001 vs. corresponding control group (Student's t-test).
Fig 6.
Effects of acute and repeated cocaine (10 mg/kg i.p.) treatment on activities of CSE (A and B) and 3-MST (C and D), enzymes which are involved in the anaerobic Cys metabolism in the rat liver and kidney.
Data are presented as the mean ± SD, n = 8–10/group, *p < 0.05, ***p < 0.001 vs. corresponding control group (Student's t-test).
Fig 7.
Effects of acute and repeated cocaine (10 mg/kg i.p.) treatment on the concentration of NO measured as the level of its stable metabolite nitrate (III) in the rat liver and kidney.
Data are presented as the mean ± SD, n = 8–10, **p < 0.01, ***p < 0.001 vs. corresponding control group (Student's t-test).