noun, plural: gonadotropins
A polypeptide hormone secreted by the anterior pituitary and the placenta, and acts primarily by stimulating the gonads and controls reproductive activity
Gonadotropin is a hormone that targets the gonads, stimulating the latter to grow and secrete sex hormones. It may be produced and secreted by the anterior pituitary, as well as by the placenta during pregnancy. Examples of gonadotropins are luteinizing hormone (LH), follicle-stimulating hormone (FSH), and placental/chorionic gonadotropins (e.g. human chorionic gonadotropin or hCG). In the anterior pituitary, gonadotropin is released by the gonadotropes, i.e. endocrine cells releasing particularly FSH and LH. hCG is produced and released by the placenta in pregnant women.
Gonadotropins are released as a response to the gonadotropin-releasing hormone (GnRH) from the arcuate nucleus and the preoptic area of the hypothalamus.
The main physiological role of gonadotropin is to stimulate the growth and the activity of the target cells. The gonadotropins act on various cell types. However, the primary target organ is the gonads (e.g. of the ovaries and the testes). Gonadotropins are essential in the regulation of the normal growth, sexual development, and reproductive activities or functions. For instance, LH stimulates target gonadal cells (e.g. males’ Leydig cells of the testes and females’ theca cells of the ovaries) to produce testosterone.
Deficiency of gonadotropin (such as in the case of pituitary disease) may lead to hypogonadism, which in turn may lead to infertility.
- gonadotropic hormone
- Pregnant mares serum gonadotropin
- Receptors gonadotropin