Figure 4: Corpus cavernosum of control and BPH rats treated with dutasteride or finasteride, and stained using picrosirius red. Samples were observed under polarized light, and images captured at ×400. These images show that all groups had a predominance of type I collagen. (a) Control group, composed of Wistar–Kyoto rats (C); (b) control animals receiving dutasteride (C + D); (c) control animals receiving finasteride (C + F); (d) group of BPH models (H); (e) group of BPH models receiving dutasteride (H + D); (f) group of BPH models receiving finasteride (H + F). Scale bars=50 μm. BPH: benign prostatic hyperplasia.