Living Reference Work Entry

Endocrinology of the Testis and Male Reproduction

Part of the series Endocrinology pp 1-22

Date: Latest Version

Anabolic and Metabolic Effects of Testosterone and Other Androgens: Direct Effects and Role of Testosterone Metabolic Products

  • Jonas ČeponisAffiliated withLos Angles Biomedical Research Institute at Harbor-UCLA Medical CenterInstitute of Endocrinology, Lithuanian University of Health Sciences
  • , Christina WangAffiliated withLos Angles Biomedical Research Institute at Harbor-UCLA Medical CenterDavid Geffen School of Medicine at UCLA, Harbor-UCLA Medical Center
  • , Ronald S. SwerdloffAffiliated withLos Angles Biomedical Research Institute at Harbor-UCLA Medical CenterDavid Geffen School of Medicine at UCLA, Harbor-UCLA Medical Center
  • , Peter Y. LiuAffiliated withLos Angles Biomedical Research Institute at Harbor-UCLA Medical CenterDavid Geffen School of Medicine at UCLA, Harbor-UCLA Medical Center Email author 

Abstract

Sex hormones play a major role throughout the body starting from gender differentiation in utero to senescence. While they are undoubtedly important for development and conservation of reproductive function, their importance has been shown in most systems by experimental and clinical models. While testosterone (T) is considered to be the most important androgen in circulation, it may either directly exert effects on target tissues or be metabolized by 5α-reductase into dihydrotestosterone (DHT) or aromatized to estradiol (E2). Differential effects of T and its metabolites are not well known and are a topic of scientific debate. These pleiotropic effects lead to variable phenotypes, clinical manifestations, and significance throughout life and may be more pronounced in some systems (such as bone and reproductive organs) or stages (such as puberty) than in others. This chapter focuses on the available clinical evidence of the androgen effects on several important systems.

Keywords

Male Androgen Testosterone Estradiol Dihydrotestosterone Effect Action Aromatase 5α-reductase Sex hormone