Objective: To investigate the effects of testosterone on the proliferation of penile corpus cavernosal cells in male SD rats.
Methods: Smooth muscle cells (SMCs) and fibroblasts collected from the corpus cavernosal tissues of male SD rats were cultured by the enzymatic dispersion method and detected for the expression of the androgen receptor (AR) by immunohistochemistry. The effects of testosterone on the SMCs and fibroblasts were observed by methyl thiazolyl tetrazolium (MTT) assay in different concentration groups (10(-8) mol/L, 10(-7) mol/L, 10(-6) mol/L, 10(-5) mol/L, 10(-4) mol/L and 10(-3) mol/L) in comparison with the control.
Results: The AR expression was found in the penile corpus cavernosal tissues. MTT assay showed that, at the concentration of 10(-5) mol/L, testosterone induced the proliferation of SMCs (68100 +/- 2200) and fibroblasts (70200 +/- 1300), with significant differences from the control ( P < 0.05), while at 10(-4) mol/L, it inhibited their proliferation (55000 +/- 1400 and 59100 +/- 1500, respectively), (P < 0.01). No significant effects were noted in the other concentration groups.
Conclusion: AR exists in the penile corpus cavernosal tissues of male rats. Testosterone modulates the proliferation of corpus cavernosum tissue cells through AR, and different concentrations of testosterone may be positively or negatively correlated with the proliferation of SMCs and fibroblasts.