TSH on surface receptor uses second messenger as
Thyroid-stimulating hormone (TSH) is a hormone secreted by the pituitary gland that controls the release of T3 and T4 by the thyroid gland.The thyrotropin receptor (or TSH receptor) is a receptor (and associated protein) that responds to thyroid-stimulating hormone(also known as "thyrotropin") and stimulates the production of thyroxine (T4) and triiodothyronine (T3). The TSH receptor is a member of the G protein-coupled receptor superfamily of integral membrane proteins and is coupled to the Gs protein.Upon binding circulating thyrotropin, a G-protein signal cascade activates adenylyl cyclase and intercellular levels of cAMP rise .cAMP activate all functional aspects of the thyroid cell, including iodine pumping; thyroglobulin synthesis, iodination, endocytosis and proteolysis; thyroid peroxidase activity; and hormone release.Ref: Ganong&;s review of medical physiology;24th edition; page no-302
cAMP
cGMP
Ca2+
IP3
Endocrinology