The effect of increasing doses of Methotrexate (Folate Antagonist) on sperm production in male Mouse

Increasing intramuscular doses of Methotrexate (25 mg / kg, 50 mg / kg, 100 mg / kg, 150 mg/ kg, 200 mg / kg, 250 mg / kg, 300 mg / kg) were tested on Swiss strain Mouse by intramuscular injection. The reproductive potency was evaluated by total sperm count and movement of the left testis and it's epididymis (15) days after injection. The weights of the latter of all tested animals were registered. The result indicate that Methotrexate, a Folate antagonist, is a negative factor for sperm production in a dose related manner. It was evident that the high doses (ex. Dose 200 mg / kg) lead to oligospermia. It was concluded that Methotrexate inhibits the reproductive potency during spermatogenesis and causes cytotoxicity in high doses. Further investigations are needed.