Basic Endocrinology

The testes secrete the steroid hormones androgens.

The main androgen secreted by the testes is testosterone, which is converted to di-hydrotestosterone in some target tissues before it can interact with intracellular receptors.

Androgens are important in sexual differentiation of the male fetus, stimulating the physical changes that occur during puberty and maintaining spermatogenesis and male secondary sex characteristics. The production of testosterone is stimulated by luteinising hormone (LH); circulating concentrations of testosterone exert negative feedback effects, regulating LH secretion.