The Human Leydig Cell
Fig. 2.1 Fetal testis. a Fetal mouse: low magnification of a semi-thin section showing seminiferous tubules (ST) and interstitial tissue (I). b Fetal mouse: higher magnification of (a) showing gonocytes (G)…
Neuroendocrine Control of Human Testicular Function
Fig. 1.1 Model depicting the role of ARC KNDy neurons in the generation of pulsatile GnRH release. KNDy neurons in the ARC nucleus form an interconnected population with their axons and/or…
Hypogonadism in Males with Congenital Adrenal Hyperplasia
Fig. 7.1 Adrenal steroid synthesis. StAR steroidogenic autoregulatory protein; SCC (cholesterol) side-chain cleavage enzyme; 3β-HSD 3β-hydroxysteroid dehydrogenase; 17β-HSD 17β-hydroxysteroid dehydrogenase Prevalence Most enzyme deficiencies that cause CAH are extremely rare, except…
Male Hypogonadism and Liver Disease
Causes of chronic liver disease Prevalence in United States Associated type of hypogonadism Nonalcoholic fatty liver disease (NAFLD) 11% Unclear, but likely more secondary Alcoholic liver disease (ALD) 2% Both…
Obesity and Aging in Late-Onset Hypogonadism
Fig. 17.1 Relationship between age and hormones. This figure shows mean hormone values at 5-year age bands with 95% confidence interval (shaded area) in 3220 European men. Mean hormone values with…
Sex Hormone-Binding Globulin and the Metabolic Syndrome
Ref. n BMI (kg/m2) Testosterone ng/dL (nmol/L) SHBG nmo/L MetS HOMA-IR Pre Post Pre Post Pre Post Pre Post Pre Post [148] 22 46.2 ± 0.9 −16.6% 340 ± 21 636 ± 186 +21.6 [149] 33 50.3 ± 6.1 31.5 ± 4.7 248 ± 91…
Androgen Replacement Therapy in Hypogonadal Men
Fig. 18.1 Who should be treated with androgen replacement therapy? Variations in sex hormone binding globulin (SHBG) gene polymorphisms and SHBG levels directly affect T levels (see Chap. 15). In genome-wide association…
Environmental Causes of Testicular Dysfunction
Fig. 14.1 Main environmental and lifestyle factors affecting testicular development and/or function in adulthood Seasonal Effects on Testicular Function Though humans are considered to be non-seasonal mammals, we are undoubtedly sensitive…
Stimulation of Spermatogenesis in Hypogonadotropic Men
Drug Trade name Application Dose Human chorionic gonadotropin (hCG) Brevactid®a Pregnylb Novarelb s.c. or i.m. 1000–2500 IU twice weekly (on Mondays and Fridays) Recombinant FSH (rFSH) Gonal F®a, Puregon®a Follistimb s.c….
Male Hypogonadism Due to Cancer and Cancer Treatments
Fig. 12.1 Effect of cytotoxic therapies on the hypothalamic–pituitary–testicular axis in children and adults. Differences in hormonal profile, cellular composition and cellular maturity can result in differential effects of cancer treatment…
