Background:

NPS-2143 is a novel and selective antagonist of CaSR (Ca2+-sensing receptor) with the EC50 value of 4.27mM for [Ca2+]o [1].

Calcilytics NPS-2143 has been reported to diminish the sensitivity of the CaSR for [Ca2+]o, resulting in an attenuated signal transduction in vitro and increased secretion of PTH in vivo. In addition, The EC50 values of NPS-2143 are 4.27, 1.56, 1.61, 2.46, 2.07 and 3.15mM for the wild-type CaSR, mutant CaSR (T151R, P221L, E767Q, G830S, and A844T), respectively. Apart from these, in HEK 293T cells expressing CaSR, NPS-2143 has been revealed to inhibit the [Ca2+]o-induced cytosolic calcium signal in a concentration-dependent manner [1].

参考文献:
[1] Letz S1, Rus R, Haag C, D?rr HG, Schnabel D, M?hlig M, Schulze E, Frank-Raue K, Raue F, Mayr B, Sch?fl C. Novel activating mutations of the calcium-sensing receptor: the calcilytic NPS-2143 mitigates excessive signal transduction of mutant receptors. J Clin Endocrinol Metab. 2010 Oct;95(10):E229-33.

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