Ca2¹²⁵ receptor ( IC50 = 43 nM )

NPS-2143 (SB-262470A) causes the plasma PTH levels in rats to quickly increase by 4 to 5 times[1]. Mean arterial blood pressure (MAP) in normotensive rats with parathyroid glands is significantly elevated by intravenous NPS-2143 (1 mg/kg) administration[2].

The HEK 293 4.0-7 clonal cell line is utilized in a high-throughput screening format to identify Ca²⁺2+ receptor agonists and allosteric activators. A quantitative and functional evaluation of the Ca²⁺2+ receptor activity in these cells Ca²⁺n be obtained by measuring changes in the concentration of cytoplasmic [Ca²⁺2+]i. The outcomes of this assay are comparable to those obtained using a homologous expression system of bovine parathyroid cells. Using a fluorescence imaging plate reader or a specially designed spectrofluorimeter, HEK 293 4.0-7 cells loaded with either fura-2 or fluo-3 Ca²⁺n have their fluorescence measured continuously and online. The concentration of extracellular Ca²⁺2+ is increased from 1.0 mM to 1.75 mM after NPS-2143 has been incubated with cells for one minute. Individual NPS-2143 tests are conducted at concentrations ranging from 20 μM to 80 μM, with those that inhibit the control response by more than 40% deemed biologiCa²⁺lly active. Concentration-response curves are used to ascertain the potencies (IC50) of NPS-2143 with biologiCa²⁺l activity. Following this, an initial evaluation of selectivity is conducted by examining the effects of NPS-2143 at a concentration several times that of its IC50 on [Ca²⁺2+]i evoked by other G protein-coupled receptors. The activation of intracellular Ca²⁺2+ is correlated with the expression of thrombin, bradykinin, and ATP receptors in wild-type HEK 293 cells as well as HEK 293 4.0-7 cells. To evaluate a compound's nonselective action on G protein-coupled receptors quickly, these responses Ca²⁺n be examined. Other assays for selectivity involve using HEK 293 cells that have been modified to express receptors that are most similar to the Ca²⁺2+ receptor in terms of topology and sequence. These comprise GABABRs (gamma-aminobutyric acid type B) and various metabotropic glutamate receptors, either native or chimeric. In order to couple to the activation of phospholipase C and the release of intracellular Ca²⁺2+ in HEK 293 cells, chimeric receptors are synthesized using partial sequences of metabotropic glutamate receptors and Ca²⁺2+ receptors. In an iterative process, NPS-2143 lacking pan-activity are then exposed to structural modifiCa²⁺tions, and their potencies and selectivities are tracked using these HEK 293 4.0-7 cell assays.

Calcilytics NPS-2143 has been shown to reduce the CaSR's sensitivity to [Ca2+]o, which attenuates signal transduction in vitro and increases PTH secretion in vivo. Furthermore, for the wild-type CaSR and mutant CaSR (T151R, P221L, E767Q, G830S, and A844T), respectively, the EC50 values of NPS-2143 are 4.27, 1.56, 1.61, 2.46, 2.07, and 3.15 mM. In addition to this, it has been shown that NPS-2143 inhibits the [Ca2+]o-induced cytosolic calcium signal in HEK 293T cells expressing CaSR in a concentration-dependent way.

[1]. Calcilytic compounds: potent and selective Ca2+ receptor antagonists that stimulate secretion of parathyroid hormone. J Pharmacol Exp Ther. 2001 Oct;299(1):323-31.

[2]. Hypertensive effect of calcilytic NPS 2143 administration in rats. J Endocrinol. 2006 Oct;191(1):189-95.

[3]. Involvement of the calcium-sensing receptor in human taste perception. J Biol Chem. 2010 Jan 8;285(2):1016-22.

[4]. Calcium-sensing receptor mediates dietary peptide-induced CCK secretion in enteroendocrine STC-1 cells. Mol Nutr Food Res. 2012 May;56(5):753-60.

[5]. Calcium-sensing receptor: a sensor and mediator of ischemic preconditioning in the heart. Am J Physiol Heart Circ Physiol. 2010 Nov;299(5):H1309-17.

C24H25CLN2O2

408.92

408.16

C, 70.49; H, 6.16; Cl, 8.67; N, 6.85; O, 7.82

284035-33-2

NPS-2143 hydrochloride; 324523-20-8

Solid powder

CC(C)(CC1=CC2=CC=CC=C2C=C1)NC[C@H](COC3=C(C(=CC=C3)Cl)C#N)O

PZUJQWHTIRWCID-HXUWFJFHSA-N

InChI=1S/C24H25ClN2O2/c1-24(2,13-17-10-11-18-6-3-4-7-19(18)12-17)27-15-20(28)16-29-23-9-5-8-22(25)21(23)14-26/h3-12,20,27-28H,13,15-16H2,1-2H3/t20-/m1/s1

2-chloro-6-[(2R)-2-hydroxy-3-[(2-methyl-1-naphthalen-2-ylpropan-2-yl)amino]propoxy]benzonitrile

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Solubility in Formulation 1: ≥ 2.5 mg/mL (6.11 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 2.5 mg/mL (6.11 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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Solubility in Formulation 3: 2% DMSO +Corn oil : 10mg/mL

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 (Please use freshly prepared in vivo formulations for optimal results.)