SPERM CAPACITATION AND HYPERACTIVATION

这项工作的长期目标是确定精子如何运动 以及鞭毛运动模式如何影响 精子到达受精点并穿透卵母细胞。我们 已经将我们的努力集中在一种称为过度激活的运动模式上， 因为已经观察到它发生在输卵管部位附近 受精。我们在这一点上的三个具体目标如下： (1)通过比较能力来研究过度激活的功能 被激活(精子在射精中的运动模式)和 过度激活的精子产生拉开精子的力量 输卵管壁和穿透透明带。拉力 将通过确定握持所需的相对力进行比较 将激活和过度激活的精子放到吸引器上。分区 穿透力将通过比较顶体- 反应性激活和高度激活的精子在体外穿透透明带。 (2)表征细胞内游离钙离子升高的机制 ([Ca~(2+)]In)，以诱导过度激活。根据我们的观察，我们 一种不同的机制调节钙内流的假设 与过度激活相关的比与顶体相关的 反应。钙通道的特征可以通过它们对 各种有机试剂和离子。我们有能力估计 个体运动过程中不同区域内钙离子浓度的变化 精子。这些技术可以用来确定一个代理是否 在影响运动的同时，实际上也会影响[钙]i。(三)确定 精子鞭毛内钙离子水平是否受 输卵管或透明带。我们观察到，过度激活是 在附着在输卵管壁上的精子中启动，只有 过度活跃的精子鞭毛可能受输卵管或卵泡的调节 透明质膜。我们已经观察到在精子中启动了过度激活 它们附着在输卵管壁上，只有过度激活 精子从壁上解放出来。另有报道称， 当精子与小带结合时鞭毛跳动的模式发生改变 透明质膜。我们假设输卵管壁和/或 Zona通过影响[Ca~(2+)]i来调节精子鞭毛搏动。[Ca2+]In 将在单个精子附着到输卵管时进行测量 上皮细胞和透明带。所获得的信息可用于 治疗不孕不育，监测毒素和疾病对 生育能力，并制定在生育之前采取的避孕方法 受精。

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.