SPERM INTERACTION WITH FALLOPIAN-TUBE APICAL MEMBRANE ENHANCES SPERM MOTILITY AND DELAYS CAPACITATION

Objective: To understand the effect of sperm contact with the apical p lasma membrane of tubal epithelial cells on sperm motility, velocity, and capacitation. Design: Prospective, controlled in vitro study. Sett ing: University medical center. Patient(s): Women of reproductive age undergoing hysterectomy for benign gynecologic indications and normozo ospermic donors of proved fertility. Main Outcome Measure(s): Sperm mo tility as measured manually, velocity as measured by computer-assisted sperm motility analysis, and capacitation status as measured by the c hlortetracycline fluorescence assay. Result(s): Sperm incubated with a pical membrane vesicles had a significantly higher motility at 12 (87. 4% +/- 3.4% versus 69.2% +/- 4.8% [mean +/- SEM]), 24 (85.2% +/- 3.1% versus 60.5% +/- 7.2%) and 48 hours (78.9% +/- 5.3% versus 42.4% +/- 1 1.3%) compared with control (sperm incubated with human tubal fluid me dia in the absence of apical membrane vesicles) (n = 4). Progressive v elocity was significantly higher at 12 (78.2 +/- 1.4 versus 61.7 +/- 1 6.1 mu m/s) and 24 (66.2 +/- 3.9 versus 34.4 +/- 9.8 mu m/s) hours (n = 4). Incubation with apical membrane vesicles significantly slowed th e transition from uncapacitated to capacitated chlortetracycline fluor escence pattern (n = 5). Conclusion(s): Contact with the apical plasma membrane of tubal epithelial cells enhances sperm motility and delays sperm capacitation in vitro. (C) 1997 by American Society for Reprodu ctive Medicine.