Fig. 5. Effect of PDGF-BB on mesenchymal mesonephric cell proliferation. Immunoselected quiescent mesenchymal cells were treated for 16-18 hours with PDGF-BB (various concentrations) and [3H]TdR (1 µCi/well). Results are mean±s.d. of four independent experiments, each done in quadruplicate. *P<0.01 vs untreated control.