SPERM CAPACITATION AND HYPERACTIVATION

精子获能和过度激活

• 批准号: 3316955
• 负责人: Susan Stevens Suarez
• 金额: $ 11.02万
• 依托单位: UNIVERSITY OF FLORIDA
• 依托单位国家: 美国
• 财政年份: 1985
• 资助国家: 美国
• 起止时间: 1985-04-01 至 1996-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3316955
• 关键词: acrosome; calcium channel; calcium flux; cilium /flagellum motility; egg /ovum; epithelium; fallopian tubes; fertilization; hamsters; ion transport; membrane activity; sperm; sperm capacitation; sperm motility; videotape /videodisc

The long-term objectives of this work are to determine how sperm movement is regulated and how flagellar movement patterns affect the ability of sperm to reach the site of fertilization and penetrate the oocyte. We have focussed our efforts on a movement pattern termed hyperactivation, because it has been observed to occur in the oviduct near the site of fertilization. Our three specific aims at this point are as follows: (1) Investigate the functions of hyperactivation by comparing the ability of activated (the movement pattern of sperm in the ejaculate) and hyperactivated sperm to generate force for pulling away from the oviductal wall and for penetrating the zona pellucida. Pulling forces will be compared by determining the relative force required to hold activated and hyperactivated sperm onto suction micropipets. Zona penetration will be tested by comparing the rates at which acrosome- reacting activated and hyperactivated sperm penetrate zonae in vitro. (2) Characterize the mechanism that raises intracellular free Ca2+ ([Ca2+]in) to induce hyperactivation. Based on our observations, we hypothesize that a different mechanism regulates the calcium influx associated with hyperactivation than that associated with the acrosome reaction. Calcium channels can be characterized by their response to various organic agents and ions. We have the ability to estimate concentrations of [Ca2+]in in various regions of individual, moving sperm. These techniques can be used to determine whether an agent actually affects [Ca2+]in while it is affecting motility. (3) Determine whether levels of [Ca2+]in in sperm flagella may be regulated by the oviduct or zona pellucida. We have observed that hyperactivation is initiated in sperm that are attached to the oviductal wall and that only hyperactivated sperm flagella may be regulated by the oviduct or zona pellucida. We have observed that hyperactivation is initiated in sperm that are attached to the oviductal wall and that only hyperactivated sperm free themselves from the wall. It has also been reported that the pattern of flagellar beating alters when sperm bind to the zona pellucida. We hypothesize that elements in the oviductal wall and/or zona regulate sperm flagellar beating by affecting [Ca2+]in. [Ca2+]in will be measured in individual sperm as they attach to oviductal epithelium and to the zona pellucida. The information gained may be used to treat infertility, to monitor the effects of toxins and disease on fertility, and to develop methods of contraception that act prior to fertilization.

这项工作的长期目标是确定精子运动是如何 以及鞭毛运动模式如何影响 精子到达受精部位并穿透卵母细胞。 我们 把精力集中在一种叫做超激活的运动模式上， 因为已经观察到它发生在输卵管中， 受精 我们目前的三个具体目标如下： (1)通过比较超激活的能力来研究超激活的功能 激活（精子在射精中的运动模式）， 超活化精子产生的力量拉离 输卵管壁和用于穿透透明膜。 拉力 将通过确定保持所需的相对力来进行比较 激活和过度激活的精子到抽吸微量移液管上。 Zona 将通过比较顶体- 反应活化和超活化精子在体外穿透透明带。 (2)表征提高细胞内游离Ca 2+的机制 ([Ca2+]in）以诱导超活化。 根据我们的观察，我们 假设有不同的机制调节钙内流 与超活化相关的比与顶体相关的 反应 钙通道可以通过它们对以下物质的反应来表征： 各种有机试剂和离子。 我们有能力估计 [Ca 2 +]浓度在不同区域的个人，移动 精子 这些技术可用于确定代理是否 在影响运动性的同时也影响[Ca 2 +]。 (3)确定 精子鞭毛中[Ca ~（2+）]in的水平是否受 输卵管或透明管。 我们已经观察到，过度激活是 起源于附着在输卵管壁上的精子， 超活化精子鞭毛可能受输卵管或输卵管的调节， 透明的 我们观察到精子开始过度激活 它们附着在输卵管壁上， 精子会从壁中释放出来 另据报道， 当精子与鞭毛结合时，鞭毛跳动的模式发生改变 透明的 我们推测输卵管壁和/或输卵管上皮细胞中的成分可能与输卵管上皮细胞的生长有关。 精子鞭毛的跳动是通过影响[Ca ~（2+）]来调节的。 [Ca2+]在 将在单个精子附着在输卵管时进行测量 上皮和透明质膜。 所获得的信息可用于 治疗不孕症，监测毒素和疾病对女性的影响 生育能力，并制定避孕方法， 受精