Effects of aqueous Cynanchum wilfordii extract (CWW) on serum (a) dihydrotestosterone (DHT) and (b) testosterone levels. *** p < 0.005, ** p < 0.01, and * p < 0.05 vs. the BPH/vehicle group. BPH: benign prostatic hyperplasia; Sham/vehicle: sham-operated and phosphate-buffered saline (PBS), oral (p.o.); BPH/vehicle: testosterone, subcutaneous (s.c.) and PBS, p.o.; BPH/finasteride: testosterone, s.c. and finasteride 5 mg/kg, p.o.; BPH/CWW 50: testosterone, s.c. and CWW 50 mg/kg, p.o.; BPH/CWW 100: testosterone, s.c. and CWW 100 mg/kg, p.o.; BPH/CWW 200: testosterone, s.c. and CWW 200 mg/kg, p.o.