G Protein-coupled Estrogen Receptor Antibodies

The CaS (Calcium-sensing receptor) is a class C G protein–coupled receptor that plays a central role in extracellular calcium homeostasis. Pharmacologically, CaS is activated primarily by extracellular Ca²⁺ ions, as well as other polyvalent cations and certain amino acids that act as allosteric modulators. Upon activation, CaS couples mainly to Gq/11 and Gi/o proteins, leading to phospholipase C activation, intracellular calcium mobilization, inhibition of adenylyl cyclase, and modulation of MAPK signaling pathways. CaS is highly expressed in the parathyroid glands and kidneys, where it regulates parathyroid hormone secretion and renal calcium reabsorption, and it is also found in bone and the gastrointestinal tract. Clinically, CaS is targeted by calcimimetics such as Cinacalcet and Etelcalcetide, which act as positive allosteric modulators and are used to treat secondary hyperparathyroidism. Negative allosteric modulators, known as calcilytics, have been investigated for osteoporosis and related disorders, although none are widely approved. Ongoing structural and pharmacological research aims to develop more selective CaS modulators with improved safety and efficacy profiles. For more information on CaS receptor pharmacology please refer to the IUPHAR database. For further reading refer to:

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