Human Biochemistry Volume 2 - Murray R. 1993

Biochemistry of Intracellular and Intercellular Communications
Sex Gland Hormones
Testicular Hormones

Testes are bifunctional Organs that produce testosterone (the male sex hormone) and spermatozoa (Male Germ Cells). These Functions are performed by three specialized Cell types: 1) spermatogonia and more differentiated germ cells located within the seminiferous tubules; 2) Leydig cells (also referred to as interstitial cells), which are scattered in the Connective Tissue between the convoluted seminiferous tubules and produce testosterone in response to LH; and 3) Sertoli cells, which form the basement membrane of the seminiferous tubules. Sertoli cells provide the nutrient environment necessary for the differentiation and maturation of germ cells; specifically, under METABOLISM/18.html">The Influence of FSH, they secrete androgen-binding protein (ABP). Spermatogenesis is stimulated by the Peptide Hormones FSH and released by the Pituitary Gland. For this process to take place, an environment that Supports germ Cell Differentiation and a higher testosterone concentration than that in the systemic Circulation are required. These conditions are met through the local secretion of ABP and testosterone by Sertoli cells and Leydig cells, respectively.