Hedrih Andjelka, Banić Milan
Department for Bio-Medical Science, State University of Novi Pazar, Vuka Karadzica bb, 36 300 Novi Pazar, Serbia.
Department for Mechanical Design, Development and Engineering, Mechanical Engineering Faculty, University of Nis, Aleksandra Medvedeva 14, 18000 Nis, Serbia.
J Theor Biol. 2016 Mar 21;393:32-42. doi: 10.1016/j.jtbi.2015.12.031. Epub 2016 Jan 15.
Although a large proportion of biomolecules involved in spermatozoa-oocyte interaction has been discovered so far, many details of fertilization mechanism remain unknown. Both biochemical and biomechanical components exist in the fertilization process. Mammalian sperm evolved a ZP (zona pelucida) thrust reduction penetration strategy probably in response to the ZP resilient elasticity. Using a biomechanical approach and FEM analysis, local contact stress, ZP deformations during impact and attempt of sperm head penetration relative to different sperm impact angles (SIA) were studied. The sperm-oocyte contact was defined as non-linear frictional contact. A transient structural analysis at 37°C revealed that, from the mechanical standpoint there are SIA that are more favorable for possible ZP penetration due to larger equivalent stress of ZP. An "slip-stick" resembling effect was identified for almost all examined SIA. The sperm head-ZP contact area increases as SIA decreases. Favorable ZP-stress state for sperm penetration regarding SIA are discussed.
尽管到目前为止已经发现了很大一部分参与精子 - 卵母细胞相互作用的生物分子，但受精机制的许多细节仍然未知。受精过程中存在生化和生物力学成分。哺乳动物精子可能为了应对透明带（ZP）的弹性，进化出了一种降低ZP推力的穿透策略。使用生物力学方法和有限元分析，研究了局部接触应力、精子头部撞击时ZP的变形以及相对于不同精子撞击角度（SIA）的精子头部穿透尝试。精子 - 卵母细胞接触被定义为非线性摩擦接触。在37°C下进行的瞬态结构分析表明，从力学角度来看，由于ZP的等效应力较大，存在一些更有利于ZP可能穿透的SIA。几乎所有检查的SIA都识别出了类似“滑 - 粘”的效应。随着SIA减小，精子头部与ZP的接触面积增加。讨论了关于SIA的有利于精子穿透的ZP应力状态。
