HCG

Third-Party Tested

Independent lab verified

Batch-Specific CoA

Publicly accessible

YPB.256

Reference number

10,000 IU

Lyophilized vial

Origin

Human Chorionic Gonadotropin (hCG) was first identified in the 1920s by Aschheim and Zondek, who detected a gonadotropic substance in the urine of pregnant women. It is naturally produced by trophoblast cells of the placenta and shares structural homology with luteinizing hormone (LH), follicle-stimulating hormone (FSH), and thyroid-stimulating hormone (TSH).

Research Lineage

hCG has been used in reproductive medicine research since the 1930s. Pierce and Parsons determined its two-subunit structure (alpha and beta chains) in the 1960s-70s. It is one of the most extensively studied glycoprotein hormones, with applications in fertility research, Leydig cell stimulation studies, and diagnostic assay development.

Mechanism of Action

hCG binds to the LH/CG receptor (LHCGR) on gonadal cells, activating the cAMP/PKA signaling cascade. In Leydig cell models, this stimulates steroidogenesis. The beta subunit confers receptor specificity, while the alpha subunit is shared with LH, FSH, and TSH. Its longer half-life compared to LH (~24-36 hours vs ~20 minutes) is due to greater sialylation.

Structural Notes

Heterodimeric glycoprotein. Alpha subunit: 92 amino acids. Beta subunit: 145 amino acids. Molecular weight: ~36,700 Da (glycosylated).