Bovine ovarian follicular fluids modulate the release of transaminases, acrosome reaction and motility of the rabbit sperm in vitro.

摘要

Ovarian follicular fluids were collected from 46 pairs of cattle ovaries. Normal follicles were classified, according to their diameter, as small (? mm), medium (4-8 mm) or large (>8 mm). Cystic follicles (diameter >20 mm, no luteal tissue) were also collected. Follicular fluids were aspirated, centrifuged and frozen until used. Two concentrations (20 and 40%) of follicular fluid from each category were tested. Rabbit semen was collected, diluted with Earle's balanced salt solution with 0.097 g/litre pyruvate and incubated in a CO2 incubator at 37鳦. Addition of follicular fluids significantly (P<0.01) decreased sperm motility. As the diameter of follicles increased, the reduction in motility decreased (P<0.01). Fluid from cystic follicles causedthe greatest reduction in motility. As the time of incubation increased there was a sharp decline (P<0.01) in motility. Addition of follicular fluids increased (P<0.01) the percentage of acrosome reaction (16.7, 16.3, 17.1 and 20.1% for fluid from large, medium, small and cystic follicles respectively compared with 13.1% for semen samples not treated with follicular fluid). A linear increase (P<0.01) in the percentage of acrosome-reacted spermatozoa was observed with increasing incubation time (13.3, 15.3, 17.2 and 22.1% at 0, 1, 2 and 4 h respectively). The release of aspartate aminotransaminase and alanine aminotransaminase was significantly (P<0.01) increased by treatment with follicular fluid and with time of treatment. Alanine aminotransaminase release was influenced (P<0.01) by the concentration of follicular fluid; 40% follicular fluid caused greater increases in the release of alanine aminotransferase than 20% follicular fluid. The concentration of follicular fluid did not affect the secretion of aspartate aminotransaminase. Cystic follicular fluid increased the release of both enzymes. A positive correlation between secretion of these enzymes and percentage of acrosome-reacted spermatozoa was observed. A significant (P<0.01) negative correlation was found between sperm motility and acrosome reaction.