[The dependence of the quantity of silver granules detectable in interphase nuclei after the silver nitrate staining of the chromosomal nucleolus-organizer regions on the conditions for the hypotonic treatment of the cells and the effect on this index of cell treatment by a pharmacological agent causing dissociation of the nucleolar components].

We investigated effects of hypotonic treatment of cultured HL-60 cells and human fibroblasts, and of DRB on the quantity of AgNORs revealed following AgNO3 staining. The average number of grains increases after KCl hypotonic treatment. The lower the concentration of KCl in the solution, the higher the number of silver grains revealed in the nucleoli due to their dissociation into substructures. The use of adenosine analogue (DRB) before the hypotonic treatment of cells facilitates the following count of silver deposits. A maximum increase in the mean number of silver grains was observed after a 1.5 h incubation.