The Sound of Evolution
Protirelin
Mechanism of action:
Protirelin is a synthetic thyrotropin-releasing hormone and is a tripeptide. Protirelin binds to the thyrotropin-releasing hormone receptor on thyrotropic cells in the anterior pituitary, and this receptor is a Gq/11 protein-coupled receptor. After activation, the receptor stimulates phospholipase Cβ, increases IP3/DAG, raises cytosolic calcium concentration, and activates protein kinase C, leading to the secretion and release of thyroid-stimulating hormone into the bloodstream, which in turn stimulates the thyroid gland to secrete T4 and T3.
Reference(s):
Yang F et al. (2022). Structural insights into thyrotropin-releasing hormone receptor activation by an endogenous peptide agonist or its orally administered analogue. Cell Research.