OBJECTIVE: To explore the result of gefitinib-coated balloon suppressive action on the excessive hyperplasia of intima after balloon injury of common carotid artery in rats and on the PI3K/AKT signal pathway. mitigated the cell apoptosis in TUNEL. The expressions of MMP9, TGFand IL6 mRNA in the model group were obviously up-regulated; and they were obviously down-regulated in the high-dose gefitinib-coated balloon group compared with the model group. CONCLUSIONS: Gefitinib-coated balloons were able to suppress the excessive proliferation in ABT-737 the common carotid arterial intima of rats more effectively than the paclitaxel-coated ones. The underlying mechanism may cover the ABT-737 PI3K/AKT signal pathway. generation of antineoplastic drug, is a selective inhibitor on epidermal growth factor receptor tyrosine kinase (EGFR-TKIs). Proliferative SMCs and endothelial cells have been found to be able to express more EGFR than those in the resting state. Also, the preliminary studies revealed that gefitinib could selectively suppress SMCs proliferation, and a selective cytotoxic effect in a dose-related degree was also observed in the endothelium and SMCs?[2]. Thus, the expressions of Caspase-3 and Bcl-2 apoptosis-related proteins were measured experiments to observe its suppressive effect on the excessive hyperplasia in intima of rats after their carotid common arteries were injured by balloons. Besides, the relevant mechanism of the intimal hyperplasia inhibition was investigated. Numerous ABT-737 studies showed that, PI3K-AKT signal pathway, a vital signal transduction pathway inside the cells, once being appropriately activated, can protect proliferation, migration and apoptosis of SMCs effectively?[3, 4]. PI3K/AKT signal method acts among the important downstream EGFR sign pathways also, and EGFR-TKIs inhibitor continues to be ABT-737 confirmed to have the ability to suppress Anpep the activation of PI3K-AKT sign pathway to regulate cell growth, proliferation and apoptosis according to the available research results?[5, 6, 7, 8, 9]. For the P-AKT as the activation state of AKT, its measurement can reflect AKTs total amount?[10]. TGF-and IL6 are involved in vascular remodeling mechanisms?[11, 12, 13]. Some studies showed EGFR-TKIs inhibitor can suppress MMP9 and TGF-expression by suppressing PI3K-AKT signaling pathway activation to reduce the proliferation of easy muscle cells?[14, 15]. This study aimed to investigate whether gefitinib-coated balloons could suppress cell proliferation or facilitate cell apoptosis by suppressing PI3K/AKT signal pathway activity and affect the intimal hyperplasia, which hinders the onset of restenosis after PCI. 2.?Basic experimental reagents and methods 2.1. Reagents and animals Hematoxylin, and TUNEL kit (Wellbio company, China). Chloral hydrate (Shanghai Shan Pu chemical company, China). Two-Step Kit (Golden Bridge Company, China). HRP Goat anti-rat IgG, BCLrabbit polyclonal antibody (catalog numbers: 12789-1-AP, Proteintech Group, US). PCNA rabbit polyclonal antibody (catalog numbers: 10205-2-AP, Proteintech Group, US). Caspase-3 rabbit polyclonal antibody (catalog numbers: 19677-1-AP, Proteintech Group, US). Gefitinib and Taxol (Meilun biological company, China). The PTCA balloon catheter (2.5F) and 1 mm balloon guideline wire (Limited by Medtronic, Inc. US); P-AKT rabbit polyclonal antibody (SC: 514032, Ser 473, Santa Cruz Biotechnology, Inc, US), PI3K rabbit polyclonal antibody (SC: 293172,Santa Cruz Biotechnology, Inc, US); RT-Kit, Ultra SYBR Mixture and 100 bp DNA Marker (Com Win Biotech Co, Ltd, China). Rat aortic endothelial cells and easy muscle cells (iCell, China). MTT kit (Beijing Saichi biotechnology company, China). DMEM medium culture fluid (Hyclone company, US). Fetal bovine serum and all the remaining reagents (Sigma, US). Fifty adult male Sprague-Dawley (SD) rats (weighing about 350 400 g) were provided by the Experimental Pet Middle of South China College or university (China). All experimental protocols had been accepted by NanHua Universitys Review Committee for the usage of Pet Topics. 2.2. Cell civilizations The.