Calcium-Sensing Receptor

NPS-2143 is a selective Ca2+-sensing receptor antagonist, shown to block increases in cytoplasmic Ca2+ concentrations elicited by human Ca2+ receptors expressed in HEK293 cells with an IC50 of 43 nM.

NPS-2143 hydrochloride (SB-262470A hydrochloride), an orally active calcilytic agent, is a selective and potent calcium ion-sensing receptor (CaSR) antagonist.

SB-423557 is an orally active calcium-sensing receptor (CaR) antagonist (IC50=520 nM), precursor of SB-423562 (IC50=73 nM).