ANALYSIS OF THE LIPID-CONTENT AND THE MOTILITY OF HUMAN SPERM AFTER FOLLICULAR-FLUID TREATMENT

The effect of human follicular fluid (hFF) on the cholesterol and phos pholipid content and the movement characteristics of human spermatozoa were studied. Semen was selected by a discontinuous Percoll gradient and incubated during in vitro capacitating conditions with B2 medium s upplemented with hFF 20%. Percoll pelleted spermatozoa were incubated in either B2 (B2-Percoll) or B2 supplemented with hFF (hFF-Percoll). I n hFF-Percoll, we observed a time-dependent (24 h) decrease in both th e cholesterol and phospholipid contents (cholesterol: 10.1 vs. 8.7 nmo l 10(-7) spermatozoa; phospholipids: 17.5 vs. 15.7 nmol 10(-7) spermat ozoa, P<0.05). This decrease in cholesterol and phospholipids in human spermatozoa was concomitant with a high straight line velocity, a hig h progressive motility percentage and an increased value of lateral he ad displacement without any significant alteration of the spermatozoal membrane. No modification of the cholesterol: phospholipid ratio afte r 2 and 24 h of incubation in either B2-Percoll (0.61, 0.54) in hFF-Pe rcoll (0.59, 0.63) was observed when compared with original control se men. It is suggested that the decrease in cholesterol and phospholipid s in hFF-Percoll may be taken into account for the changes of membrane modification as part of the capacitation process.