addition of cyclic amp or dibutyryl cyclic amp in low concentration ( 10 ( -8 ) to 10 ( -10 ) m ) also enhanced colony numbers although concentrations above 10 ( -5 ) m were inhibitory . enhancement was found when marrow cells were pre-treated with these agents and cultured in their absence .
C0001455
cyclic amp
C0012054
dibutyryl cyclic amp