Investigation of pig sperm plasma membrane reorganization using progesterone-albumin-fluorescein probes

ObjectiveTo relate semen susceptibility in cooling protocols to sperm plasma membrane properties.MethodsA series of experiments was performed using the fluorescent markers, progesterone-BSA-FITC and BSA-FITC.ResultsThese experiments indicated that both progesterone-BSA-FITC and BSA-FITC bound to specific sperm plasma membrane domains, thus producing four different binding patterns, revealing probable changes in membrane organization during capacitation and during cooling. Those patterns seem to make a sequence progressing from non-capacitated status to capacitated status. The proportion of each pattern was different during incubation than during cooling, showing the latter had a higher proportion of dead sperm than the former.ConclusionsAt this stage, the association of sperm plasma membrane alterations was revealed by BSA-FITC probes and cryosensitivity remains unclear.