Study On Effection Of Propranolol And Isoproterenol On Hemangioma Of Infant In Vitro

Objective:1) To investigate the effects of propranolol and isoproterenol on thegrowth curve of infantile hemangioma endothelial cells (IHECs) in vitro and determinethe functions of the β-adrenergic receptor in the pathogenesis of infantile hemangioma;2)To investigate the effects of propranolol and isoproterenol on vascular endothelial growthfactor (VEGF), vascular endothelial growth factor-2(VEGF-2) and basic fibroblastgrowth factor (bFGF) in vitro;3) To investigate the effects of propranolol andisoproterenol on β-adrenergic receptor-2(β2-AR) in vitro;4) To investigate the effects ofpropranolol and isoproterenol on apoptosis of IHECs. Methods: IHECs were divided intothree groups:The control group, the propranolol group (PG) and the isoproterenol group(IG). The PG and IG were administered with high, medium and low concentrations of thecorresponding drugs. The cell growth in each group was determined using the MTT assay.Then IHECs were cultured in a certain concentration of propranolol and isoproterenol forcertain period of time (24～48hours), then testing the VEGF, VEGF-2, bFGF and β2-ARby ELISA. At last testing the cell apoptosis rate after cultured in certain concentrationpropranolol and isoproterenol by flow cytometry. Result: High propranolol concentrationresulted in the inhibition of cell growth (P＜0.05). By comparison, isoproterenolpromoted cell growth (P＜0.05). Within a specific time frame, high drug concentrationselicited strong effects on the cells. At certain concentrations, propranolol inhibited cellgrowth once the proliferation stage of IHECs had been affected for a specific length oftime, whereas isoproterenol yielded opposite results. The concentration of VEGF,VEGF-2, bFGF and β2-AR were differet with before the drug use. The propranololdecreased the concentration of these infectors and β2-AR, whereas isoproterenol yieldedopposite results. The effect were related with the time and drug concentration. After24hours, the apoptosis rate of IHECs in high concentration propranolol group (20μg/ml) were increased (P＜0.05),48hours later the medium concentration group were alsoincreased (P＜0.05), whereas isoproterenol yielded opposite results. Conclusion: Part1The propranolol of certain concentration can inhibit the growth of IHECs in vitro, and theisoproterenol is just opposite. The β-adrenergic receptor elicits an important effect in thepathogenesis of infantile hemangioma. The propranolol can decrease the concentration ofthe VEGF, VEGF-2, bFGF and β2-AR, and isoproterenol can increase them. The effect ofpropranolol and isoproterenol on apoptosis rate of IHECs were just opposite. So Theβ-adrenergic receptor elicits an important effect in the pathogenesis of infantilehemangioma, maybe it was related with the cytokine and cell apoptosis rate.