Fig. 4

Skin-derived precursors Schwann cells protected the smooth muscle content and prevented the fibrosis process in corpus cavernous. A Masson trichrome staining of penile cross section tissues specimen of each group. Red and blue represented muscle and collagen content respectively. B Immunofluorescence staining for desmin(green) in penile cross section tissues specimen. C Quantitative analysis of Masson trichrome staining results. The ratio of collagen to smooth muscle showed the degree of fibrosis. D Quantitative analysis of the desmin immunofluorescence positive area. All the data were depicted as mean ± standard deviation from 5 animals per group. **p < 0.01; the student’s unpaired t-test was used for two-group comparisons; multiple-group comparisons were carried out by one-way ANOVA followed by the S–N-K test