Unesterified cholesterol content of human sperm regulates the response of the acrosome to the agonist, progesterone.
Unesterified cholesterol content of human sperm regulates the response of the acrosome to the agonist, progesterone.
复制标题
人类精子中的未酯化胆固醇含量调节顶体对激动剂黄体酮的反应。
DOI：
10.1095/biolreprod55.1.19
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发表时间：
1996
影响因子：
3.6
通讯作者：
Cross,NL
中科院分区：
文献类型：
--
作者：
Zarintash,RJ;Cross,NL
人精子经洗涤去除精浆后，在适当的培养基中培养，对顶体反应诱导剂有反应。我们测试了精子在孵化过程中必须失去胆固醇才能对激动剂孕酮产生反应的假设。新鲜射出的精子含有2.92 ± 0.202 nmol未酯化胆固醇/107个精子（平均值± SEM，n = 18）。当在体外孵育24 h时，精子悬浮液损失29 ± 6%的游离胆固醇（n = 23）。精子失去胆固醇的速度略快于它们对顶体反应的速度。在培养基中加入胆固醇可以防止精子失去胆固醇，从而防止精子对胆固醇产生反应。改变培养基的胆固醇含量对精子胆固醇损失（ED 50 = 406 nM）和顶体反应性（ED 50 = 388 nM）具有相似的影响。将精子与1：150稀释的精浆（含有5.18 μ M胆固醇）一起孵育也可以防止精子失去胆固醇并变得敏感。将精子在含有0.5 mg/ml磷脂酰胆碱的培养基中孵育24 h，可增加胆固醇损失量和响应性精子数量。我们的研究结果支持一种模型，其中精子未酯化胆固醇（或与它平衡的分子）抑制顶体反应。精子必须失去未酯化的胆固醇才能对孕酮产生反应。
Human sperm become responsive to inducers of the acrosome reaction if they are washed free of seminal plasma and incubated in an appropriate medium. We tested the hypothesis that sperm must lose cholesterol during incubation in order to become responsive to the agonist, progesterone. Freshly ejaculated sperm contained 2.92 ± 0.202 nmol unesterified cholesterol/107sperm (mean ± SEM, n = 18). When incubated for 24 h in vitro, sperm suspensions lost 29 ± 6% of their free cholesterol (n = 23). Sperm lost cholesterol slightly faster than they became acrosomally responsive. Adding cholesterol to the medium prevented sperm from losing cholesterol and from becoming responsive. Varying the cholesterol content of the medium had similar effects on loss of sperm cholesterol (ED50= 406 nM) and acrosomal responsiveness (ED50= 388 nM). Incubating sperm with a 1:150 dilution of seminal plasma (containing 5.18 microM cholesterol) also prevented sperm from losing cholesterol and from becoming responsive. Incubating sperm 24 h in medium containing 0.5 mg/ml phosphatidylcholine increased the amount of cholesterol lost and the number of sperm that became responsive. Our results support a model in which sperm unesterified cholesterol (or a molecule in equilibrium with it) suppresses acrosomal responsiveness. Sperm must lose unesterified cholesterol to become responsive to progesterone.