title: An involvement of neurokinin-1 receptor in FcεRΙ-mediated RBL-2H3 mast cell activation.
abstract: OBJECTIVE
  To determine whether the neurokinin-1 receptor (NK1R) plays a role in the activation of RBL-2H3 mast cells after FcεRΙ aggregation.
  
  
  METHODS
  NK1R expression in RBL-2H3 cells was inhibited by small hairpin RNA (shRNA) against NK1R, and determined by western blotting. For activation, both NK1R knockdown and control RBL-2H3 cells were sensitized by dinitrophenol (DNP)-specific IgE and stimulated with the antigen DNP-bovine serum albumin (BSA). Following the activation of RBL-2H3 cells, monocyte chemoattractant protein (MCP-1) production and intracellular calcium flux were monitored by ELISA and confocal microscopy assay, respectively. For investigation of the signaling mechanism, phosphorylation of mitogen-activated protein kinases (MAPKs) after RBL-2H3 cell activation was assessed by western blotting.
  
  
  RESULTS
  shRNA-NK1R mediated an effective inhibition of NK1R expression in RBL-2H3 cells. Protein production of MCP-1 was reduced by more than 55 % in NK1R knockdown RBL-2H3 cells compared with control RBL-2H3 cells. In addition, both calcium mobilization and phosphorylation levels of MAPKs (Erk1/2, JNK, and p38) after DNP-BSA stimulation (via FcεRΙ) were decreased due to the inhibition of NK1R expression.
  
  
  CONCLUSIONS
  NK1R is required for the activation of RBL-2H3 cells following FcεRΙ engagement and involved in the regulation of MAPK signaling pathways.
authors: The Key Laboratory of Molecular Medicine, Ministry of Education, Shanghai 200032, People's Republic of China.
authors: Xiaoyun
authors: X
authors: Fang
authors: Hua
authors: H
authors: Hu
authors: Jianhui
authors: J
authors: Xie
authors: Haiyan
authors: H
authors: Zhu
authors: Dongmei
authors: D
authors: Zhang
authors: Wei
authors: W
authors: Mo
authors: Ruxin
authors: R
authors: Zhang
authors: Min
authors: M
authors: Yu
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism; D045744:Cell Line, Tumor; D018932:Chemokine CCL2 / Q000378:metabolism; D055785:Gene Knockdown Techniques; D008407:Mast Cells / Q000378:metabolism*; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000235:genetics; D051381:Rats; D017455:Receptors, IgE / Q000378:metabolism*; D018040:Receptors, Neurokinin-1 / Q000235:genetics / Q000378:metabolism*
chemical_list: C491766:Ccl2 protein, rat; D018932:Chemokine CCL2; C553474:FCER1A protein, rat; D034741:RNA, Small Interfering; D017455:Receptors, IgE; D018040:Receptors, Neurokinin-1; D020928:Mitogen-Activated Protein Kinases; D002118:Calcium