Changes in cyclic nucleotide levels during erythroid differentiation in Friend leukemia cells

Changes in cyclic nucleotide levels were observed in Friend leukemia cells exposed to the inducers of erythroid differentiation dimethylsulfoxide (DMSO), sodium butyrate and hypoxanthine. The most extensive changes in cAMP levels occurred during the initial 24 h growth period. In uninduced cultures, cAMP concentration increased 35-fold compared with a 7-fold increase in the presence of inducer. During the same period. cGMP levels rose about 3-fold in uninduced cells compared with a 20-fold increase in induced cells.