(A, B) BMP2 mRNA levels in C2C12 cells, treated with PTH at 0 to 200 nM for 12 hours (A); or PTH at 50 nM for 0 to 12 hours (B), were measured by real time PCR with GAPDH normalization. * p<0.01 (vs vehicle; mean±SE, n = 6). (C) BMP2 promoter reporter activity in C2C12 cells, transfected with −2712/+165-Luc and treated with PTH at 0 to 200 nM for 24 hours, was measured with β-gal normalization. * p<0.01 (vs vehicle; mean±SE, n = 8). (D) BMP2 promoter reporter activity in C2C12 cells, co-transfected with CREB plasmid or vector and reporter −2712/+165-Luc, and treated with IBMX at 50 µM or KT5720 at 5 µM for 24 hours, was measured. * p<0.01 (CREB vs vector); # p<0.01 (CREB+IBMX vs CREB+vehicle); ** p<0.05 (CREB+KT5720 vs CREB+vehicle; mean±SE, n = 8). (E) BMP2 mRNA levels in calvrial cells, isolated from CREB cKO and control mice, and treated with PTH at 50 nM for 24 hours, were measured by real time PCR. * p<0.01 (cKO vs control); # p<0.01 (PTH on cKO vs PTH on control); ** p<0.05 (PTH vs vehicle on control mice; mean±SE, n = 6); NS: not significant.