Neonatal rat hepatocytes in primary tissue culture free from density-dependent regulation of growth.

Studies employing [3H]thymidine and radioautography as well as colchicine and Feulgen staining of DNA showed that up to 19-fold increases in the degree of cell crowding in vitro, i.e. from 1.45 to 27.55 X 10(4) cells per specimen, did not change the rates of entry into DNA synthesis and mitosis of cultivated primary neonatal rat hepatocytes.