В. И. Трухачев The terminal sections of chromosomes, where ribosomal RNAs entering the cytoplasm and participating in the formation of ribosomes are synthesized, are considered to be a criterion of cell activity for protein synthesis. These chromosome regions are detected by silver nitrate and are called zones or regions of the nucleolar organizers (AgNORs). Morphometric analysis of the nucleolar organizer regions allows evaluating the protein-synthetic function of cells, reflecting the degree of their differentiation and proliferation, and can also be used to assess the duration of a cell cycle. Using the silver nitrate impregnation technique, the authors studied the activity parameters of the nucleolar organizer regions and, based on them, evaluated the protein-synthetic function of turkey kidney podocytes in postnatal ontogenesis. The object of the study was 60 clinically healthy males and females of the North Caucasian white breed, aged 1 month, 2 months, 3 months, 4 months, 5 months, and 6 months. It has been established that the number of regions of the nucleolar organizers in the nuclei of turkey kidney glomerular podocytes ranges from 1 to 4, with the largest number being recorded at the age of three to five months of life, and at the age of one, two, and six months they are fewer. The area of the nucleolar organizer region in the nuclei of turkey podocytes, and, consequently, the synthesis of ribosomal RNA, is wave-like and depends on the gender, age, and kidney location, however, lower values of this indicator are recorded in the period from the first to the second month of life.
Научная статья 
ribosomal RNA