title: The effect of friction and impact angle on the spermatozoa-oocyte local contact dynamics.
abstract: 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.
authors.affiliation: Department for Bio-Medical Science, State University of Novi Pazar, Vuka Karadzica bb, 36 300 Novi Pazar, Serbia. Electronic address: handjelka@hm.co.rs.
authors.forename: Andjelka
authors.initials: A
authors.lastname: Hedrih
authors.affiliation: Department for Mechanical Design, Development and Engineering, Mechanical Engineering Faculty, University of Nis, Aleksandra Medvedeva 14, 18000 Nis, Serbia.
authors.forename: Milan
authors.initials: M
authors.lastname: Banić
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D005260:Female; D020342:Finite Element Analysis; D017276:Friction; D008297:Male; D051379:Mice; D008954:Models, Biological; D009865:Oocytes / Q000502:physiology*; D011312:Pressure; D013084:Sperm-Ovum Interactions / Q000502:physiology*; D013094:Spermatozoa / Q000502:physiology*; D013314:Stress, Mechanical; D013696:Temperature; D013997:Time Factors; D015044:Zona Pellucida / Q000502:physiology
keywords: Biomechanics; Finite element method; Local strain; Sperm impact angle; Zona pellucida