Effect of dehydroleucodine on the reproductive tract of male mice.

The effects of a sesquiterpene lactone, dehydroleucodine, on the reproductive tract were investigated using adult male mice. Dehydroleucodine was dissolved in tap water and administered as drinking water for 30 days. All the parameters were compared with a control group that received only vehicle. Animals were killed by decapitation and the trunk blood, the testes and the epididymes were collected. Plasma concentrations of testosterone and oestradiol, and testicular weight and concentration of spermatids did not change by dehydroleucodine. Nevertheless, in epididymal cauda dehydroleucodine treatment caused a diminution in sperm number, a decrease in the amount of tubular fluid and a reduction in the activity of the hydrolytic enzyme N-acetyl-β-d-glucosaminidase. However, the sperm motility was not altered by dehydroleucodine treatment, although sperm binding to zona-free oocytes increased significantly. These results suggest that dehydroleucodine, which has been implicated in the inhibition of aromatase P450, does not affect the plasma concentration of testosterone and oestradiol or testicular activity, whereas altering several epididymal parameters. The epididymis is thus a more sensitive target for dehydroleucodine action.