The hydrodynamic radii (nm) of blood serum particles of low, medium, high and ultra-high molecular weight and their contribution to light dissipation were registered under conditions of treatment course with Heptral and MIGU-1 hepatoprotectors. These results were compared with results of well-known medicament Essenciale. It was ascertained that LCS method is valuable in diagnosis of hepatoprotective activity of new medicaments MIGU-1 and Heptral in comparison with well-known Essenciale. Heptral introduction in the dose of 20 mg/kg leads to particles with hydrodynamic radius 2–11 nm appearing on the histogram. These particles appeared to be a fraction of low-weight proteins – albumins and globulins. The results were different from those with 40 mg/kg dose. It was showed that in the case of immunization with ram’s erythrocytes particles with ultra-high hydrodynamic radii appear on the histogram. That indicates formation of circulating immune complexes.
