Semen liquefaction is a proteolytic process where a gel-like ejaculated semen becomes watery due to the enzymatic activity of prostate-derived serine proteases in the female reproductive tract. The liquefaction process is crucial for the sperm to gain their motility and successful transport to the fertilization site in Fallopian tubes (or oviducts in animals). Hyperviscous semen or failure in liquefaction is one of the causes of male infertility. Therefore, the biochemical inhibition of serine proteases in the female reproductive tract after ejaculation is a prime target for novel contraceptive development. Herein, we will discuss protein components in the ejaculates responsible for semen liquefaction and any developments of contraceptive methods in the past that involve the liquefaction process.

中文翻译：

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精液液化机制及其作为新型非激素避孕药的潜力†。

精液液化是一种蛋白水解过程，由于女性生殖道中前列腺来源的丝氨酸蛋白酶的酶活性，凝胶状射出的精液变成水样。液化过程对于精子获得活力并成功运输到输卵管（或动物输卵管）的受精部位至关重要。精液粘稠或液化失败是男性不育的原因之一。因此，射精后女性生殖道中丝氨酸蛋白酶的生化抑制是新型避孕药开发的主要目标。在这里，我们将讨论精液中负责精液液化的蛋白质成分，以及过去涉及液化过程的避孕方法的发展。