We thank Dr. Horacio B. Croxatto from the Instituto Chileno de Medicina Reproductiva for his valuable comments in the preparation of this manuscript. This work received financial support from grants CONCYTEC 628 DE-89 and 2043 DE-91, and FONDECYT 1030315.

This investigation was supported by a grant from the Sciences and Technology National Council (CONCYTEC, project No. 2043), Lima-Peru.

Acknowledgments -This investigationw as supportedb y a grant from the Sciences and Technology National Council (CONCYTEC, Project No 2043) Lima-Peru.

Benign Prostatic Hyperplasia (BPH) affects, worldwide, 50% of 60-year-old men. The Peruvian plant red maca (Lepidium meyenii) inhibits BPH in rodents. This study aimed to determine the effects of methanolic red maca extract and its n-butanol and aqueous fractions on expression of androgen and oestrogen receptors in rats with testosterone enanthate-induced BPH. Thirty-six rats in six groups were studied. Control group received 2 mL of vehicle orally and 0.1 mL of propylene glycol intramuscularly. The second group received vehicle orally and testosterone enanthate (TE) (25 mg/0.1 mL) intramuscularly in days 1 and 7. The other four groups were BPH-induced with TE and received, during 21 days, 3.78 mg/mL of finasteride, 18.3 mg/mL methanol extract of red maca, 2 mg/mL of n-butanol fraction, or 16.3 mg/mL of aqueous fraction from red maca. Treatments with red maca extract and its n-butanol bu...