title: A comparison of the effects of nifedipine, verapamil, and low-molecular-weight heparin on SLIGRL-NH₂-induced calcium influx through proteinase-activated receptor 2 activation.
abstract: BACKGROUND
  Proteinase-activated receptor 2 (PAR2) may be implicated in skin disorders. Intracellular calcium mobilization is a key step in PAR2-induced signaling.
  
  
  OBJECTIVE
  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 Ca(2+).
  
  
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Pharmacy, General Hospital of Jinan Military Region, Jinan, PR China.
authors.forename: Jun
authors.initials: J
authors.lastname: Sun
authors.forename: Wei
authors.initials: W
authors.lastname: Dou
authors.forename: Hong
authors.initials: H
authors.lastname: Shen
authors.forename: Jinhong
authors.initials: J
authors.lastname: Hu
mesh_terms: D002118:Calcium / Q000378:metabolism*; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D057809:HEK293 Cells; D006495:Heparin, Low-Molecular-Weight / Q000494:pharmacology; D006801:Humans; D009543:Nifedipine / Q000494:pharmacology; D009842:Oligopeptides / Q000494:pharmacology*; D044464:Receptor, PAR-2 / Q000378:metabolism*; D014700:Verapamil / Q000494:pharmacology
chemical_list: D002121:Calcium Channel Blockers; D006495:Heparin, Low-Molecular-Weight; D009842:Oligopeptides; D044464:Receptor, PAR-2; C112356:seryl-leucyl-isoleucyl-glycyl--arginyl-leucinamide; D014700:Verapamil; D009543:Nifedipine; D002118:Calcium