NPS-2143 is a novel potent and selective antagonist of Ca(2+) receptor with IC50 of 43 nM.

NPS 2143 blocks increases in cytoplasmic Ca2+ concentrations with IC50 of 43 nM elicited by activating the Ca2+ receptor in HEK 293 cells expressing the human Ca2+ receptor.NPS 2143 stimulates parathyroid hormone (PTH) secretion from bovine parathyroid cells with EC50 of 41 nM. Moreover, NPS 214 also blocks the inhibitory effects of calcimimetic NPS R-467 on PTH secretion from bovine parathyroid cells and the inhibitory effects of extracellular Ca2+ on isoproterenol-stimulated increases in cyclic AMP formation.In HEK-293 cells transiently expressing hCaSRs, NPS 2143 significantly suppresses the kokumi taste by effectively inhibiting the activity of both GSH (data not shown) and γ-Glu-Val-Gly.A recent study shows that NPS 2143 treatment suppresses low molecular weight fractions of azuki hydrolysate-induced cholecystokinin (CCK) secretion in CaSR-transfected HEK 293 cells.

In rats, NPS 2143 results in a rapid 4- to 5-fold increase in plasma PTH levels and also a transient increase in plasma Ca2+ levels.In normotensive rats, NPS 2143 administration (1 mg/kg) by i.v. markedly increases mean arterial blood pressure (MAP) in the presence of parathyroid glands.

Cinacalcet 

Cinacalcet hydrochloride   

NPS-2143  

Strontium Ranelate

PF-543 hydrochloride

PF-04449913