Differentiation of 3T3-L2 fibroblasts into adipose cells in bromodeoxyuridine-suppressed cultures.

Growth of 3T3-L2 fibroblasts in medium containing 5-bromo-2'-deoxyuridine prevents the spontaneous cytodifferentiation of these cells into adipose cells. Treatment of bromodeoxyuridine-suppressed cultures at confluence with 1-methyl-3-isobutylxanthine, a promoter of the adipose conversion, results in differentiation of the fibroblasts into adipose cells but the extent of the conversion is less than that seen in cultures not treated with bromodeoxyuridine. 1-Methyl-3-isobutylxanthine appears to function without altering the amount of bromodeoxyuridine present in DNA.