ABSTRACT
PIP: In Guadalajara and Mexico City, Mexico, researchers collected and analyzed semen samples from fertile men who were sexually abstinent for 3 days to evaluate the effect heparin has on sperm nuclear decondensation patterns and motility. They used 3 sesquiterpene-lactones to inactivate the thiol groups on the outer membrane of sperm cells: I (17, 18 dehydroviguiepinin), II (Budlein A), and III (Zaluzanin A). Sesquiterpene-lactones I, II, an III had an inhibitory effect of 81%, 73%, and 27%, respectively, 6 hours after the sperm had been incubated with heparin for 6 hours. First mixing the sperm with reduced glutathione before adding 17, 18 dehydroviguiepinin increased the decondensating effect of heparin 350% above that of sperm not incubated with both glutathione and heparin. Sperm motility fell 80%, 60%, and 16%, respectively, 15 minutes after incubation with sesquiterpene-lactones I, II, and III. When sperm was incubated with heparin only, sperm motility was consistently higher for 5 hours. None of the compounds used to incubate the sperm affected sperm viability. The findings provided more information about the molecular biology of mammalian spermatozoa and suggested that sesquiterpene-lactones may be effective male contraceptives.^ieng