Green D P, Purves R D
Biophys J. 1984 Apr;45(4):659-62. doi: 10.1016/S0006-3495(84)84207-1.
Sperm have generally been supposed to penetrate the zona pellucida surrounding the mammalian egg with the aid of a protease, acrosin. Difficulties associated with this view are discussed and an alternative, mechanical hypothesis introduced. The calculated force exerted by individual sperm is too small to permit the rupture of any but the weakest of secondary chemical bonds. Mechanical progress through the zona must rely on stress relaxation in a viscoelastic medium. The known properties of the zona appear to be consistent with such a mechanism of penetration.
一般认为，精子是借助一种蛋白酶——顶体素，穿透围绕哺乳动物卵子的透明带的。本文讨论了与这一观点相关的难点，并提出了另一种机械假说。计算表明，单个精子施加的力太小，除了最弱的二级化学键外，无法使其他化学键断裂。精子在透明带中的推进必须依靠粘弹性介质中的应力松弛。透明带的已知特性似乎与这种穿透机制相一致。
