Aim: To clarify the mechanism of the therapeutic action of icariin on erectlile dysfunction (ED). Methods: PDE5 was isolated from the human platelet and PDE4 from the rat liver tissue using the FPLC system (Pharmacia,...Aim: To clarify the mechanism of the therapeutic action of icariin on erectlile dysfunction (ED). Methods: PDE5 was isolated from the human platelet and PDE4 from the rat liver tissue using the FPLC system (Pharmacia, Milton Keynes, UK) and the Mono Q column. The inhibitory effects of icariin on PDE5 and PDE4 activities were investigated by the two-step radioisotope procedure with [3H]-cGMP/[3H]-cAMP. Papaverine served as the control drug. Results: Icariin and papaverine showed dose-dependent inhibitory effects on PDE5 and PDE4 activities. The IC50 of Icariin and papaverine on PDE5 were 0.432 μmol/L and 0.680μmol/L, respectively and those on PDE4, 73.50 μmol/L and 3.07μmol/L, respectively. The potencies of selectivity of icariin and papaverine on PDE5 (PDE4/PDE5 of IC50) were 167.67 times and 4.54 times, respectively. Conclusion: Icariin is a cGMP-specific PDE5 inhibitor that may be developed into an oral effective agent for the treatment of ED.展开更多
结合湖南省吉怀高速公路吉怀七标太阳冲大桥40 m T梁的架设安装实例,介绍了小曲线半径大纵坡桥梁在架设安装上应注意的事项,通过合理的选用架梁设备,改进架梁施工工艺,使40 m T梁在小曲线半径大纵坡桥梁上架设安装安全得以保证,为以后...结合湖南省吉怀高速公路吉怀七标太阳冲大桥40 m T梁的架设安装实例,介绍了小曲线半径大纵坡桥梁在架设安装上应注意的事项,通过合理的选用架梁设备,改进架梁施工工艺,使40 m T梁在小曲线半径大纵坡桥梁上架设安装安全得以保证,为以后山区高速公路该类桥梁架设安装提供借鉴。展开更多
文摘Aim: To clarify the mechanism of the therapeutic action of icariin on erectlile dysfunction (ED). Methods: PDE5 was isolated from the human platelet and PDE4 from the rat liver tissue using the FPLC system (Pharmacia, Milton Keynes, UK) and the Mono Q column. The inhibitory effects of icariin on PDE5 and PDE4 activities were investigated by the two-step radioisotope procedure with [3H]-cGMP/[3H]-cAMP. Papaverine served as the control drug. Results: Icariin and papaverine showed dose-dependent inhibitory effects on PDE5 and PDE4 activities. The IC50 of Icariin and papaverine on PDE5 were 0.432 μmol/L and 0.680μmol/L, respectively and those on PDE4, 73.50 μmol/L and 3.07μmol/L, respectively. The potencies of selectivity of icariin and papaverine on PDE5 (PDE4/PDE5 of IC50) were 167.67 times and 4.54 times, respectively. Conclusion: Icariin is a cGMP-specific PDE5 inhibitor that may be developed into an oral effective agent for the treatment of ED.
