Physiology of Testosterone Production

  • Joseph W. McQuaid
  • Cigdem Tanrikut


Androgens play an essential role in the development of male reproductive organs, the maintenance of male fertility, and the preservation of secondary male sexual characteristics. The production of testosterone, the dominant circulating androgen, is a finely balanced process with many points of potential regulation, starting with the translocation of cholesterol across the mitochondrial membrane and ending with the negative feedback of testosterone at level of the hypothalamus and the pituitary gland. This chapter explores the physiology of testosterone production, beginning with its intracellular synthesis and steroidogenic conversion, and then follows testosterone’s transport across the cell membrane and into circulation. Regulation of this system via the hypothalamic–pituitary–testis axis is reviewed. Finally, this discussion concludes with two increasingly prevalent clinical circumstances in which testosterone physiology is altered: the metabolic syndrome and the aging male.


Luteinizing Hormone Sertoli Cell Leydig Cell Congenital Adrenal Hyperplasia Luteinizing Hormone Level 
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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  1. 1.Department of UrologyMassachusetts General HospitalBostonUSA
  2. 2.Department of UrologyMGH Fertility Center, Massachusetts General Hospital, Harvard Medical SchoolBostonUSA

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