AG 18

AG 18 (Tyrphostin 23) is an inhibitor of epidermal growth factor receptor (EGFR) and platelet-derived growth factor receptor (PDGFR) kinase with IC50 values of 35 and 25 μM respectively. AG 18 inhibits EGF-stimulated cell proliferation. AG 18 also acts as a mitochondrial uncoupler that alters phosphorylation-dependent cell signaling. AG18 increased the rate of oxygen consumption and reduced cellular ATP by approximately 90% in the absence of the muscarinic agonist carbachol. AG 18 (10 μM) decreases the potency of 5-HT 4-fold and reduces the maximal contraction to 5-HT in the carotid artery. AG18 blocked parotid phosphorylation events only at concentrations that reduced ATP content. AG18 (RG-50810) also activated AMPK and/or uncoupled mitochondria in PC12, HeLa, and HEK293 cells.