With this study, the determination of three spectra of medium molecular peptides (SMP) in liver tissue can provide a basis for ideas about the relationship between exogenous and endogenous proteins, the degree of damage to nucleotides and proteins, and enable certain judgments to be made. It is also aimed to obtain information about the level of detoxification processes in hepatocytes against the background of 60% deficiency of exogenous input of casein protein.