Fig. 1.
Stimulation of Epo production in P19 cells by RA.
Epo concentration in the spent medium and the total cellular proteins were determined. Epo production is given as nanograms of Epo per milligram cellular protein. (A) P19 cells were cultured with or without the indicated substances at 5 × 10−7 mol/L for 36 hours. (B) P19 cells were cultured with the indicated concentrations of all-trans RA for 48 hours in monolayers (■) and aggregate cultures (▪). Each value is the mean ± SD of triplicate experiments.
