Experiments were carried out using 69 rabbit males with a body mass of 2.5-3.0 kg. Experimental allergic polyneuritis developed in the animals after administration into foot pads of the base neuritogenic proteins together with complete Freund's adjuvant. Content of cholesterol (CS) and triglycerides (TG) was increased more than 2-fold, concentration of the total fraction of beta- and pre- beta-lipoproteins was elevated 3-fold in blood plasma of rabbits within 1 hr after the treatment. Within 12 days after administration of the mixture another increase in the fractions studied was observed, reaching the maximal value within the 30 days of the experiment: content of cholesterol and triglycerides was increased 3-fold, total fraction beta- and pre- beta-lipoproteins--more than 4-fold. The ratio CS/TG was similar in blood sera of both normal and injured rabbits and was approximately equal to 0.4. The increase in permeability of aortal wall and its lipid infiltration were found at the same period.