[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.

[Study of blood cholesterol and triglycerides in patients with acute myocardial infarction].

The levels of cholesterol (C) and triglycerides (TG) were studied by a standard biochemical assays and the amount of C and TG was examined by a fluorescence assay in 55 patients with complicated (n=32) and uncomplicated (n=23) acute myocardial infarction (AMI) and in 25 apparently healthy donors. The content of C did not differ significantly in the study groups. As compared with the controls, the patients with complicated AMI had lower values of C + TG (p < 0.

Autofluorescence of low-density lipoproteins modified as a result of autooxidation.

Autooxidation of low-density lipoproteins during incubation at 37 degrees C was accompanied by accumulation of LPO products, decrease in UV autofluorescence (FUV), and increase in autofluorescence in the visible band (FVIS). The degree of low-density lipoprotein modification was estimated by calculating the FVIS/FUV ratio. A positive correlation was revealed between this ratio and concentration of thiobarbituric acid-reactive LPO products (r=0.

[Analysis of the amount of plasma cholesterol and triglycerides in patients with coronary heart disease].

Fluorescence technique was used to study the time course of changes in the amount of blood cholesterol and triglycerides (C+TG) in 43 patients with Q- and non-Q-wave myocardial infarction (MI) on days 1, 2, 3, and 10 of the disease, in 82 patients with chronic coronary heart disease (CHD), and in 43 apparently healthy donors. Within the first 3 days of the disease, the level of C+TG in the patients with acute MI (AMI) was significantly lower than that in the patients with chronic CHD and in the donors. By day 10 of their hospital stay, the level of lipids in patients with AMI increased and reached the levels observed in the control group.

Changes in surface charge of low-density lipoproteins during oxidative modification.

The negative surface charge of low-density lipoproteins increased during their oxidative modification induced by autooxidation at 37 degrees C. The degree of changes depended on the time of autooxidation: the surface charge remained practically unchanged after short-term oxidation (6-h incubation), but then progressively increased and after 24-h oxidation it 2-fold surpassed the initial level. Long-term incubation of low-density lipoproteins in the presence of EDTA inhibiting lipid peroxidation did not change their surface charge.