Fig. 3. Effects of natriuretic peptide receptor 2 (NPR2) knockdown on cyclic guanosine monophosphate (cGMP) production and cell proliferation in mouse Leydig cells. (A and B) The NPR2 expression in mRNA and Western blot levels in mouse Leydig transducted with shRNA-NPR2 lentivirus. (C) The cGMP production in mouse Leydig cells transducted with shRNA-NPR2 lentivirus. (D) The cell activity in mouse Leydig cells transducted with shRNA-NPR2 lentivirus. (E) The mRNA expression of cyclin A1, cyclin B1, and cyclin D2 in mouse Leydig cells transducted with shRNA-NPR2 lentivirus. The β-actin was used as internal control. The protein of NPR2 were normalized to that of β-actin. The results are presented as the mean±standard error of mean and are representative of three independent experiments. ^*p<0.05 and ^**p<0.01 compared with each corresponding group in the control.