GLOSSARY

Testicular Endocrine Physiology
Testicular endocrine physiology coordinates Leydig-cell steroidogenesis with Sertoli-cell support and pituitary gonadotropin input.

Production, transport and local action. Androgen action depends on central gonadotropin drive, gonadal production, binding proteins and tissue-specific metabolism. Conversion to DHT or estradiol changes the local signal. Receptor expression and cofactors determine how exposure becomes a response in each organ.

A distinction that matters. Local testosterone exposure differs substantially from its peripheral serum concentration.

Interpreting androgen status. Symptoms, repeated appropriately timed measurements and relevant LH, FSH and SHBG results help distinguish endocrine patterns. A transient exercise-associated change does not predict hypertrophy. Exogenous androgen exposure can suppress endogenous regulation and fertility despite high circulating concentrations.