Reproductive and Hormonal Functions of the Male:
After studying this lecture you should understand:• spermatogenesis, which means simply the formation of sperm;
• performance of the male sexual act; and
• regulation of male reproductive functions by the various hormones.
Physiologic Anatomy of the Male Sexual Organs:
Spermatogenesis
Sperm
Hormonal Factors That Stimulate Spermatogenesis
1. Testosterone, secreted by the Leydig cells located in the testis, is essential for growth and division of the testicular germinal cells, which is the first stage in forming sperm.2. Luteinizing hormone, secreted by the anteriorpituitary gland, stimulates the Leydig cells to secrete testosterone.
3. Follicle-stimulating hormone FSH, also secreted by the anterior pituitary gland, stimulates the Sertoli cells; without this stimulation, the conversion of the spermatids to sperm (the process of spermiogenesis) will not occur.
4. Estrogens, formed from testosterone by the Sertoli cells when they are stimulated by FSH hormone, are probably also essential for spermiogenesis.
5. Growth hormone (as well as most of the other body hormones).
Maturation and Storage of Sperm in the Epididymis
Physiology of the Mature Sperm:
Semen
Male sexual act
Erection, Emission, and Ejaculation:
Testosterone:
Gonadotropic Hormones: LH and FSH
