低氧对大鼠精子体外顶体反应和顶体酶、透明质酸酶活性的影响

目的研究低氧对大鼠精子顶体酶、透明质酸酶活性的影响以及对精子体外顶体反应发生的影响。方法成年Wistar大鼠随机分为4个组:常氧对照组、低氧5d组、低氧15d组和低氧30d组。低氧组置低压舱内模拟高原5000m,分别低氧5、15和30d。采用明胶薄膜法、透明质酸底物转化法、溶血磷脂胆碱(LPC)诱导金霉素荧光染色法,测定低氧对附睾尾精子顶体酶、透明质酸酶活性和体外顶体反应发生率的影响。结果低氧5、15和30d组大鼠精子顶体反应发生率,与常氧对照组相比均显著降低,分别由常氧对照组的(30.5±3.5)%,下降至(11.7±0.9)%(P<0.01)、(10.8±1.0)%(P<0.01)和(10.0±1.4)%(P<0.01);低氧5、15和30d组大鼠精子顶体酶阳性率降低,分别由常氧对照组的(81.67±7.16)%,下降至(54.17±3.82)%(P<0.01)、(30.00±3.92)%(P<0.01)和(43.00±3.63)%(P<0.01);低氧各组透明质酸酶活性无显著改变(P>0.05)。结论低氧抑制了精子顶体酶活性和顶体反应发生。

Effect of hypoxia on acrosome reaction and activity of acrosin protease and hyaluronidase

Objective To explore the effects of hypoxia on the capacity of sperm fertilization in rat. Methods Male Wistar rats were randomly divided into four groups: control group, 5d hypoxic group, 15d hypoxic group and 30d hypoxic group. Control group was raised at sea level, hypoxic groups were raised in a hypobaric chamber simulating 5000m altitude for 5 days, 15 days and 30 days respectively. Acrosin protease activity and lysophosphatidyl choline (LPC)-induced acrosome reaction (AR) of sperm were detected. The hyaluronidase activity in testis was also assessed. Results The LPC-induced AR was suppressed by about 60% in all three hypoxic groups (P<0.01, compared with control group). Acrosin protease activities in three hypoxic groups were significantly lower than that in control group (P<0.01, compared with control group). Hyaluronidase activities were unchanged in three hypoxic groups. Conclusion Hypobaric hypoxia inhibits rat sperm acrosome reaction and acrosin protease activity. It indicates that hypoxia suppresses fertilization of sperm in rat.