七、小结
精子发生是一个非常错综复杂的过程,由HPG轴通过Gn RH、LH和FSH等激素分泌对其进行精确的调控。激素水平紊乱是导致男性不育的常见原因。睾丸产生精子的最佳温度低于体温2~4℃,生成成熟精子需要64d。衔接良好的生精周期和生精波可确保生精速度恒定在每秒1200个精子。精子发生是雄激素依赖性过程,依赖于较高的睾丸内睾酮水平。精子离开睾丸时并不具有运动能力,使卵母细胞受精的能力也有限。经过附睾转运后,精子获得运动和受精能力。在射精过程中,精子迅速从附睾远端进入射精管及尿道。射出的精液组分能够维持精子的新陈代谢和运动,起到抗氧化的作用,并作为屏障阻止后续精子进入卵子。
参考文献
完整的参考文献列表通过www.expertconsult.com在线获取。
推荐阅读
Akre O,Richiardi L.Does a testicular dysgenesis syndrome exist?Hum Reprod 2009;24:2053-60.[An excellent and critical review of the TDS concept].
Cornwall GA.New insights into epididymal biology and function.Hum Reprod Update 2009;15:213-27.[Upto-date review of epididymal biology].
De Jonge CJ,Barratt CL,editors.The sperm cell:production,maturation,fertilization,regeneration.New York:Cambridge University Press;2006[An up-to-date review of mammalian and human sperm biology,genetics,and function].
DiNapoli L,Capel B.SRY and the standoff in sex determination.Mol Endocrinol 2008;22:1-9.[A review of the new theory of sex determination in which“testis genes”coexist with“antitestis genes”].
Itman C,Mendis S,Barakat B,et al.All in the family:TGF-beta family action in testis development.Reproduction 2006;132:233-46.[An excellent review of HPG axis factors inhibin and activin].
Masters V,Turek PJ.Ejaculatory physiology and dysfunction.Urol Clin North Am 2001;28:363.[Review of the fundamentals of the physiology and pathology of ejaculation].
Payne AH,Hales DB.Overview of steroidogenic enzymes in the pathway from cholesterol to active steroid hormones.Endocr Rev 2004;25:947-70.[Review of the complex biology of steroid hormone production].
Robaire B,Hinton BT,editors.The epididymis:from molecules to clinical practice:a comprehensive survey of the efferent ducts,the epididymis and vas deferens.New York:Kluwer Academic and Plenum;2002[Easily the most comprehensive basic science text on the biology of the epididymis and vas deferens].
Skinner MK,Griswold MD,editors.Sertoli cell biology.San Diego:Elsevier;2005[State-of-the-art update on Sertoli cells and male reproduction].
Smith JF,Turek PJ.Ejaculatory duct obstruction.Urol Clin North Am 2008;35:221-7.[Comprehensive review of the biology,physiology,and pathology of the seminal vesicle and ejaculatory duct complex].
Turek PJ.Male infertility.In:Tanagho EA,Mc Aninch JC,editors.Smith’s urology.17th ed.Stamford(CT):Lange Clinical Medicine;2007[Basic review of human meiosis].
Turek PJ,Reijo Pera RA.Current and future genetic screening for male infertility.Urol Clin North Am 2002;29:767-92.[Comprehensive review of genetic associations with male infertility].
Walker WH.Molecular mechanisms of testosterone action in spermatogenesis.Steroids 2009;74:602.[Up-to-date review of the hormone biology of spermatogenesis].
(陈向锋 邹沙沙 马 逸 刘凯峰 编译陈慧兴 潘 峰 李 铮 审校)