In addition , in the later of 80 ' s , the results obtained in weston and suzuki ' s laboratories and other laboratories showed that a new substance , christened edhf , could be released by ach or other vasoactive substances such as substance p . and the edhf could cause hyperpolarization of the vascular smooth muscle cells in an endothelium - dependent manner 除edrf外， 80年代末weston和suzuki等发现ach等血管活性物质还可使血管内皮释放一种可使smc膜电位超极化的因子( edhf ) 。 edhf介导的血管舒张不受血红蛋白和亚甲蓝的影响，说明其作用机制与no无关。
