gonadotropines

Gonadotropins, or gonadotropines, are a group of glycoprotein hormones that stimulate the activity of the gonads. In humans, the principal gonadotropins are follicle-stimulating hormone (FSH) and luteinizing hormone (LH), produced by the anterior pituitary. A related hormone, human chorionic gonadotropin (hCG), is produced by the placenta and acts similarly to LH. Gonadotropins regulate reproductive processes through interactions with the gonads.

FSH and LH are heterodimeric glycoproteins, consisting of a common alpha subunit and distinct beta subunits, produced by pituitary gonadotrophs. hCG is also a heterodimer with a shared alpha subunit and a distinct beta subunit; it is produced by placental trophoblasts during pregnancy.

In females, FSH stimulates growth of ovarian follicles and estrogen production; LH triggers ovulation and formation of the corpus luteum, which secretes progesterone. In males, FSH supports spermatogenesis via Sertoli cells; LH stimulates Leydig cells to produce testosterone.

Secretion is regulated by gonadotropin-releasing hormone (GnRH) from the hypothalamus, released in pulses. Negative and positive feedback from sex steroids and inhibin modulates secretion. hCG is produced during pregnancy and helps maintain luteal function in early pregnancy by supporting progesterone production.

clinically, gonadotropins are used therapeutically in infertility treatments. Recombinant FSH and LH are employed for ovulation induction and controlled ovarian stimulation in assisted reproduction. hCG is used to trigger ovulation and to support the luteal phase. In men, gonadotropin therapy may treat hypogonadotropic hypogonadism. Side effects can include ovarian hyperstimulation syndrome, multiple gestations, and cardiovascular or metabolic risks, requiring careful monitoring.