ABSTRACT
One of the considerable uses of lettuce [Lactuca sativa] seed in traditional medicine has been to reduce semen, sperm and sexuality. The aim of this study was to investigate the effects of aqueous and hydro-alcoholic extracts of lettuce seed on testosterone level and spermatogenesis. In this experimental study 24 adult male NMRI mice weighing 20-25gr were purchased. Animals were randomly divided into 4 groups: controls, hydro-alcoholic [200 mg/kg] and aqueous extracts [50, 100mg/kg]. The extracts were injected intraperitoneally once a day for 10 consecutive days. 2 weeks after the last injection, the mice were anaesthetized by ether and after laparatomy blood was collected from the heart to determine testosterone by ELISA assay kit. Then testis and cauda epididymis of all animals were removed for analyzing testis morphology and sperm count and viability. Testis weight in hydro-alcoholic and aqueous extracts 100 mg/kg [p=0.001] and aqueous extract 50 mg/kg [p=0.008] groups was increased .Sperm viability in hydro-alcoholic [p=0.001] and aqueous extracts 50 [p=0.026], 100 mg/kg [p=0.045] groups was decreased, Also the results showed a significant decrease in sperm count in hydro-alcoholic [p=0.035] and aqueous extracts 50 mg/kg [p=0.006] groups in comparison with control group. Also there was a significant increase in serum level of testosterone in aqueous extract 50 mg/kg group in comparison with control [p=0.002] hydro-alcoholic [p=0.001] and aqueous extracts 100 mg/kg [p=0.003] groups. Present results demonstrated that hydro-alcoholic and aqueous 50 mg/kg extracts of lettuce seed have antispermatogenic effects, also aqueous extract 50 mg/kg increased serum level of testosterone in mice. Therefore we can suggest that lettuce seed could be a potential contraceptive agent.