R α methylhistamine dihydrochloride

Histamine and the specific histamine receptor agonists 2-([3-trifluoromethyl]-phenyl histamine dimaleate (H1R agonist), amthamine dihydrobromide (H2R agonist), and (R)α-methylhistamine dihydrochloride (H3R agonist) were from Sigma-Aldrich Corp. (St. Louis, MO, USA). The receptor agonist 4-methylhistamine dihydrochloride (H4) and TAPI-1 (ADAM17 inhibitor) were from Tocris Bioscience (Ellisville, MO, USA). EGF was from Sigma-Aldrich, and Amplex Red and fura-2-acetoxymethyl ester (fura-2/AM) were purchased from Invitrogen (Grand Island, NY, USA). An EGFR antagonist was from LC Laboratories (Tyrphostin AG 1478; Woburn, MA, USA). Antibodies directed against the EGFR, phosphorylated EGFR (Tyr1068), AKT, phosphorylated AKT, and Western blotting application solution kits were purchased from Cell Signaling Technology (Danvers, MA, USA). Antibodies against ERK and phosphorylated ERK and small interfering RNA (siRNA) transfection medium were from Santa Cruz Biotechnology (Santa Cruz, CA, USA). Transfection reagent, rat EGFR siRNA–SMART pool, and nontargeting pool were from Dharmacon RNAi Technology (DharmaFECT1, ON-TARGETplus, ON-TARGETplus, respectively; Lafayette, CO, USA).