Mitochondrial dysfunctions are an underlying cause of many human diseases including degenerative diseases. One of the consequences of mitochondrial dysfunctions is apoptosis of functionally active cells. During the initial stage of apoptosis, increased production of superoxide anion-radical (SAR) is observed. A promising method of SAR detection in cells and tissues is chemiluminescence (CL), primarily, in the presence of lucigenin, a SAR specific amplifier of CL. In this study a means of improving CL was proposed, and its effectiveness in detecting SAR level in living tissues of laboratory animals in hypoxia and parkinsonism models was evaluated. Aerobic (O₂ — 15 %, CO₂ — 5 %, N₂ — 80 %) and anaerobic (CO₂ — 5 %, N₂ — 95 %) gas mixtures proposed for samples aeration, maintained a constant pH of 7.4, necessary for accurate recording of CL. Using the studied method, a statistically significant increase (1.8 and 2.0 times) in SAR production level in rat heart tissue was detected with hypoxia duration of 150 to 240 minutes. In the parkinsonian model SAR production in mouse brain tissue samples of striatum and substantia nigra was 1.7 and 1.3 times higher after administration of the final dose of proneurotoxin, as compared to the control group.