CRAC Channel Inhibitor IV, GSK-7975A

A cell permeable pyrazol derivative that acts as a specific CRAC (Ca²⁺ release-activated Ca²⁺ entry) channel blocker (IC₅₀ = 800 nM in RBL cells) possibly downstream of STIM1 oligomerization and STIM1/Orail interaction. Shown to fully block Orail1 and at 10 µM in HeK293 cells (t_1/2 = 75-100 s), but with 2.5-fold slower than La3+ kinetically. Also inhibits Orail3 currents with similar potency but with faster kinetics (t_1/2 = ~20s). Exhibits good selectivity against a panel of more than 16 ion channels, only with reduced effects on L-type Ca²⁺ (CaV1.2) and TRPV6 channels. Inhibits store-operated Ca2+ entry (IC₅₀ = 3.4 µM) at 10 µM in normal pancreatic acinar cells, but not in pancreatic acinar cell line AR42J which has a neuronal phenotype and hepatocytes, and does not affect acetylcholine or cholecystokinin induced Ca²⁺ spiking. Shown to block palmitoleic acid ethyl ester-induced trysin and protease activitiest and abolish necrosis. Additionally, reduces Fc?RI-dependent Ca²⁺ influx, at 3 µM and reduces the release of histamine, leukotriene C4, and cytokines (IL-5/-8/-13 and TNFα) by up to 50% in human lung mast cells (HLMC) and from rat, mouse and guinea-pig preparations.

A cell permeable pyrazol derivative that acts as a specific CRAC (Ca²⁺ release-activated Ca²⁺ entry) channel blocker (IC₅₀ = 800 nM in RBL cells) possibly downstream of STIM1 oligomerization and STIM1/Orail interaction. Shown to fully block Orail1 and at 10 µM in HeK293 cells (t_1/2 = 75-100 s), but with 2.5-fold slower than La3+ kinetically. Also inhibits Orail3 currents with similar potency but with faster kinetics (t_1/2 = ~20s). Exhibits good selectivity against a panel of more than 16 ion channels, only with reduced effects on L-type Ca²⁺ (CaV1.2) and TRPV6 channels. Inhibits store-operated Ca2+ entry (IC₅₀ = 3.4 µM) at 10 µM in normal pancreatic acinar cells, but not in pancreatic acinar cell line AR42J which has a neuronal phenotype and hepatocytes, and does not affect acetylcholine or cholecystokinin induced Ca²⁺ spiking. Shown to block palmitoleic acid ethyl ester-induced trysin and protease activitiest and abolish necrosis. Additionally, reduces Fc?RI-dependent Ca²⁺ influx, at 3 µM and reduces the release of histamine, leukotriene C4, and cytokines (IL-5/-8/-13 and TNFα) by up to 50% in human lung mast cells (HLMC) and from rat, mouse and guinea-pig preparations.

Please note that the molecular weight for this compound is batch-specific due to variable water content. Please refer to the vial label or the certificate of analysis for the batch-specific molecular weight. The molecular weight provided represents the baseline molecular weight without water.

Cell permeable: yes

Primary Target
CRAC

Reversible: yes

Packaged under inert gas

Toxicity: Standard Handling (A)

Following reconstitution, aliquot and freeze (-20°C). Stock solutions are stable for up to 3 months at -20°C.

Voronina, S., et al. 2015. Biochem. J.465, 405.
Derler, I., et al. 2013. Cell Calcium.53, 139l.
Gerasimenko, J.V., et al. 2013. PNAS.110, 13186.
Louise, V., et al. 2013. Eur. J. Pharmacol.704, 49.

Ashmole, I., et al. 2012. J. Aller. Clin. Immun.129, 1628.

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