[Effect of poly-4-vinylpyridine on the quantity of colony-forming cells in the bone marrow and spleen of mice].

Administration of poly-4-vinylpyridine to mice in the maximal tolerance dose doubled the colony-forming units (CFU) and decreased the cell count by 22% in the bone marrow. The increase of CFU number takes place from 2 to 7 days. The cell count in the bone marrow began to decreased 2 hours after the administration of the polymer and remained below the initial level for 5 days; however it began to return to the normal from the second day, reaching the normal figures by the 7th day. In the spleen the CFU rose 9-fold, with a simultaneous development of splenomegaly on account of increased cell count.