Gonadotrophin

Gonadotrophin is a term used in endocrinology to refer to the pituitary glycoprotein hormones that regulate the gonads. The principal gonadotrophins in humans are follicle-stimulating hormone (FSH) and luteinizing hormone (LH).

FSH stimulates growth and maturation of ovarian follicles in females and supports spermatogenesis in males by acting on Sertoli cells. LH, in the female, triggers ovulation and the formation and function of the corpus luteum, and stimulates ovarian production of estrogen and progesterone; in males, LH stimulates Leydig cells to produce testosterone.

Secretion of FSH and LH is controlled by gonadotropin-releasing hormone (GnRH) from the hypothalamus, released in a pulsatile manner. The gonads provide negative feedback through sex steroids (estrogens, progesterone, testosterone) and inhibin, helping regulate hypothalamic-pituitary activity.

Clinically, gonadotrophins are used in the diagnosis of pituitary or hypothalamic disorders and in fertility treatment. For infertility, recombinant or urinary-derived FSH is used to induce follicle development; when LH activity is present (as in human menopausal gonadotropin, or hMG) it can assist follicular maturation. A trigger of ovulation is often provided by administration of human chorionic gonadotropin (hCG), which mimics LH. In men, gonadotrophin therapy can be used to treat hypogonadotropic hypogonadism to stimulate testosterone production and spermatogenesis. GnRH analogues and antagonists are used to modulate gonadotrophin release in various reproductive therapies and conditions.

Overall, gonadotrophins play central roles in reproductive function, and their pharmacological derivatives are important tools in medicine.