Background: Proteinase-activated receptor 2 (PAR2) may be implicated in skin disorders. Intracellular calcium mobilization is a key step in PAR2-induced signaling. Aims: In this study, we investigated the effects of nifedipine, verapamil, and low-molecular-weight heparin (LMWH) on SLIGRL-NH2-induced PAR2-mediated calcium mobilization within cells. Methods: The intracellular calcium concentration was measured with fluo-8, a fluorescence indicator for free Ca2+. Results: Our results showed that SLIGRL-NH2 induced a dose-dependent calcium influx. This calcium influx was completely blocked in HaCaT cells and significantly blocked by LMWH in HEK293/PAR2 cells. However, both nifedipine and verapamil failed to inhibit the SLIGRL-NH2-induced calcium influx in either cell line. Conclusion: These results indicate that the PAR2 activation-induced calcium mobilization was mediated by intracellular calcium stores but not by extracellular calcium present in the media.

Keywords:
Proteinase-activated receptor 2, Calcium, Low-molecular-weight heparin, Nifedipine, Verapamil
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© 2014 S. Karger AG, Basel
2014
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