HCG (Human Chorionic Gonadotropin)

Human Chorionic Gonadotropin consists of 237 amino acids in a single chain with three intramolecular disulphide bridges and is not a steroid, but a naturally occurring peptide hormone, produced by the embryo in the early stages of pregnancy and later by the trophoblast (part of the placenta) to help control a pregnant woman hormones. This makes the uterine lining ready for implantation of the fertilized egg. HCG is a glycoprotein composed of 237 amino acids and has a mass of 36.7kDa.
HCG basically acts as Luteinizing Hormone (LH) in your body and LH is a Gonadotropin.
They were first extracted from the human in 1958; more precisely the pituitary glands. A gonadotropin is any substance that stimulates the gonads (ovary, testes). It is heterodimeric (initiates prophase of mitosis) with an alpha subunit identical to LH (luteinizing hormone), FSH (follicle stimulating hormone) and TSH (thyroid stimulating hormone).
LH is as stated above is called a gonadotropin because it stimulates the gonads (testes). It is produced in the pituitary cells and is made up of a beta chain of 115 amino acids and an alpha chain of 89 amino acids. In the testes, the LH binds to receptors on the leydig cells which in turn stimulate the synthesis and secretion of testosterone. Like LH, FSH is also called a gonadotropin. It consists of a beta chain of 115 amino acids and an alpha chain of 89 amino acids, the same as LH. Production and release of FSH is controlled by GnRH (gonadotropin releasing hormone).
FSH stimulates testicular growth and supports the function of sertoli cells, which are needed for sustaining maturing sperm cells. TSH is also known as a thyrotropin and is secreted by cells in the anterior pituitary glands. TSH is comprised of a beta chain of 112 amino acids and an alpha chain of 89 amino acids. The alpha chain is the same as that found in the two other pituitary hormones, LH and FSH, and HCG as well. TSH is produced when the hypothalamus releases TRH (thyrotropin releasing hormone). TRH then causes the pituitary gland to release.TSH makes the thyroid gland produce triiodothyronine (T3) and thyroxine (T4), which controls the body’s metabolism.