Results : part 1 effect of iron on contraction in rat endothelium - denuded aortic rings ( 1 ) ferric ammonium citrate ( fac ) ( looumol / l ) caused a phasic response with an initial transient contraction followed by relaxation in thoracic aortic ring （ l ） 100pmol几拘磅酸铁（ ferricammoniumcitrate ， fac ）对血管具有直按收缩效应，可引起大鼠主动脉环发生相位性收缩。
