Bar graphs depict effects in preglomerular vascular smooth muscle cells of RACK1 siRNA versus negative control siRNA (Control) on [3H]-thymidine incorporation under low serum (0.1%) conditions (panel A), on cell number under low serum conditions (panel B) and on cell number under high serum (2.5%) conditions (panel C). [3H]-thymidine incorporation or cell number for RACK1 siRNA cells was expressed as a % of the average [3H]-thymidine incorporation or cell number for the Control cells. [3H]-thymidine incorporation in low serum Control cells was 32,477 dpm, and the cell counts in low and high serum Control cells were 73,142 and 474,500, respectively. Values represent means ± SEM, and p-values are from unpaired Student’s t-test.