[Investigation of peroxide modification of low- and very low-density lipoproteins in patients with coronary heart disease by the method of fluorescent spectroscopy].

In the total fraction of low and very low density lipoproteins (LDL+VLDL) isolated from serum by precipitation in the presence of heparin-Mn the copper-induced lipid peroxidation was accompanied by accumulation of LPO products, a decrease ANS fluorescence intensity (F(ANS)) and an increase in probe--cation DSP-6, a fluorescence intensity decrease of intrinsic in the ultraviolet area (F(uv)) and an increase in the visible area (F(vis)). The degree of lipoprotein modification was estimated by calculating the F(vis)/F(uv) and F(DSP)-6/F(ANS) ratio. Strong positive correlation was found between these ratios and concentration of thiobarbituric acid-reactive substances (TBARS) of LDL+VLDL samples isolated from sera of 49 donors and incubated at 37 degrees C in the presence of 50 M CuSO4 during 0, 3 and 24 hr (F(vis)/F(uv) (r = 0.75; p < 0.001) and F(DSP-6)/F(ANS) (r = 0.73; p < 0.001)). Very strong positive correlation was also found between both fluorescent parameters F(vis)/F(uv) and F(DSP-6)/F(ANS) (r = 0.95, p < 0.001). Changes in the values of F(vis)/ F(uv), F(DSP-6)/F(ANS), concentration of TBARS in 75 patients with documented coronary heart disease (CHD) and 49 apparently healthy donors were studied. No significant differences of these parameters in LDL+VLDL of patients with CHD and donors were found.