The development of endogenous intoxication was studied using an experimental model to predict the course of obstructive uropathy. To this end, one control and three experimental groups of animals were formed, in which blood was drawn from the marginal ear vein on the 3rd, 7th, 14th and 21st days of the experiment. The following parameters were determined in blood serum: urea, creatinine, total protein, and albumin. The level of endogenous intoxication was assessed by the indicators of medium-mass molecules, circulating immune complexes, and malondialdehyde. Statistical analysis of blood biochemical parameters and markers of endogenous intoxication confirms that these indicators are suitable as markers of the severity of the pathological process and morphofunctional changes in the tissue of the obstructed and compensatory organs. Our findings point to overstress of adaptation mechanisms, the development of oxidative stress, and reveal a high level of endogenous intoxication, resulting in structural and metabolic changes both in the affected and in the contralateral kidney.