Physiological and biochemical studies on freezability boar spermatozoa

首次研究了2-羟丙基-β-环糊精(HBCD)和甲基-β-环糊精(MBCD)对猪精子冷冻性和冷休克敏感性的影响。经环糊精处理后的精子，无论是冷休克精子还是冷冻解冻精子，其活力、前进活力和运动速度均显著高于对照组。预加胆固醇-3硫酸盐的环糊精导致上述所有指标的降低。这些观察结果表明，对其膜的人工修饰提高了猪精子对冷休克和冷冻应激的抵抗力。接下来，我们检查了冷冻前将精子暴露在精浆中是否会降低其冷冻能力，通过使用体外受精和金霉素荧光评估来评估精子的活动细胞百分比和体外穿透能力。冷冻保存时，精子在冷冻…前先在精浆中孵化与在改良的Hulsenberg VIII稀释液中孵育的精子相比，添加NG的精子在解冻后的活力水平显著降低。精子在精浆中的孵化也显著阻止了冷冻解冻后的精子穿透卵母细胞。下一个实验是使用未冷冻的精子，以确定精子与精浆孵育是否降低了冷冻前的穿透能力，导致冷冻后的穿透率明显低于没有精浆孵化的精子。未冷冻精子在精浆中孵育后穿透能力也显著降低，但精子活力在精浆处理组和改良Hulsenberg VIII稀释液处理组之间有显著差异。结果表明，精浆中含有对冷冻前精子有一定修饰作用的S因子，对冷冻后精子的冷冻能力和穿透能力有负面影响。较少

The effects of exposure to 2-hydroxyprophl-beta-cyclodextrin(HBCD) and methyl-beta-cyclodextrin(MBCD) on the freezability and cold shocked sensitivity of boar spermatozoa were investigated in the first experiment. The motility, progressive motility and velocity of either cold-shocked or frozen-thawed spermatozoa in cyclodextrin exposure treatments were significantly higher than those of the control. Preloading cyclodextrin with cholesterol-3 sulfate resulted in a decrease in all aforementioned criteria. These observations demonstrate that the artificial modification of its membrane improves the resistance of boar spermatozoa to cold shock and cryopreservation stress. We next examined whether the exposure of spermatozoa to seminal plasma before freezing decreases its freezability, assessed by %motile cells and in vitro penetration ability using IVF and chlortetracycline fluorescence assessment. When subjected to cryopreservation, the spermatozoa incubated in seminal plasma before freezi … More ng showed significantly lower levels of post-thaw motility than did spermatozoa incubated in modified Hulsenberg VIII diluents. The incubation of spermatozoa in seminal plasma also significantly prevented frozen-thawed spermatozoa from penetrating the oocytes. The next experiment, using unfrozen spermatozoa, was to determine if the incubation of spermatozoa with seminal plasma reduced the penetration ability before freezing, resulting in a significantly lower penetration rate after freezing compared with spermatozoa incubated without seminal plasma. The penetration competence of unfrozen spermatozoa was also found to be significantly decreased by incubation in seminal plasma, but to difference in motility was observed between the treatments with seminal plasma and modified Hulsenberg VIII diluents. It was concluded that ejaculated seminal plasma contains some factor(s) that modified the sperm before freezing, negatively influence the freezability and penetration competence of spermatozoa after freezing. Less