Objective To investigate the clinical significance of the plasma adrenomedullin(ADM) and endothelin(ET-1) concentrations in patients with serious injuries complicated by hemorrhagic shock.Method Plasma ADM and ET-1 concentrations were measured by radioimmunoassay in 38 hemorrhagic shock patients(A group)and 36 non-hemorrhagic shock patients(B group)among 74 serious injury patients in the early stage and 30 age-sexmatched healthy(C group) control subjects.Results Plasma ADM and ET-1 concentrations in B group and A group,including mild(A_1 group),middle(A_2 group) and serious(A_3 group) hemorrhagic shock patients were significantly higher than those of C group.The plasma ADM and ET-1levels were greatly higher in A group than in B group.Their levels in A_1,A_2 and A_3 groups were progressively increased.There were statistical differences between A_1 and A_2 group,A_1 and A_3 group,A_2 and A_3 group respectively.There were similar increases of the plasma ET-1/ADM ratio in A group,and the ratios in A_1,A_2 and A_3 group were progressively increased also.There were positive correlations between increased plasma ADM levels and the increased plasma ET-1 levels in both A group and B group patients(r=0.492,0.438,P