title: The use of strontium-substituted media for capacitating human spermatozoa: an improved sperm preparation method for the zona-free hamster egg penetration test.
abstract: An improved procedure for human sperm capacitation based upon calcium deprivation using a modified Tyrode's medium is described. Replacement of CaCl2 by SrCl2 significantly increased the penetration of zona-free hamster eggs after 20 hours of sperm preincubation, compared with parallel sperm aliquots incubated in normal medium. The effect of an extra 4 hours' sperm preincubation produced no significant shift in fertilizing ability. Addition of 0.1 mM ethyleneglycol-bis-(beta-amino-ethyl ether)-N,N,N',N'- tetraacetic acid (EGTA) to the strontium-substituted medium resulted in a further significant increase in the penetration rate as well as a significant increase in polyspermy. The average increase in the penetration capacity (penetration rate X polyspermy) of the strontium/EGTA-preincubated spermatozoa was approximately tenfold, with no significant shift as a result of an extra 4 hours' preincubation.
mesh_terms: D000818:Animals; D002118:Calcium / Q000502:physiology; D006224:Cricetinae; D004533:Egtazic Acid / Q000494:pharmacology; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D013075:Sperm Capacitation / Q000187:drug effects*; D013081:Sperm Motility / Q000187:drug effects; D013084:Sperm-Ovum Interactions / Q000187:drug effects*; D013324:Strontium / Q000494:pharmacology*; D015044:Zona Pellucida / Q000502:physiology
chemical_list: D004533:Egtazic Acid; D002118:Calcium; D013324:Strontium