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

Objective: This study was to investigate the effects of MEHP on isolated rat heart and explore its mechanism. Methods: The experiments were performed with Langendorff-perfused rat heart with a Langendorff apparatus. 35 SD rats were used in the experiment and there were 5 rats per group. MEHP at doses of 3.125, 6.250, 12.500 and 25.000 μmol/L were given to the hearts for 25 minutes. Effects of NAC at concentration of 5 mmol/L were evaluated by co-treatment with 12.500 or 25.000 μmol/L MEHP. Data was collected per 5 minutes for 25 minutes. The heart rate, LVDP, LVEDP, dp/dtmax, and dp/dtmin were measured and analyzed using a PL3508 Data Acquisition and Analysis System. 200 waves at least were required each time. LDH contents in heart lavage fluid were determined by photometric assays using the automated biochemical analyzer. A section of the heart tissue was used for histopathological examination. DCFH-DA method was used to detect the levels of reactive oxygen species in different groups of heart tissues. Results: There was a concentration dependent decrease of heart rate (P<0.05) . At concentrations of 6.250, 12.500 and 25.000 μmol/L, MEHP significantly decreased the LVDP, dp/dtmax and dp/dtmin (P<0.05) , and this decrease is more pronounced with perfusion time. As the MEHP was given up to 6.250, 12.500 and 25.000 μmol/L, a statistical significance was found in the increase of LVEDP (P<0.05) . For dp/dtmin, a significant increase was observed at the concentration of 3.125 μmol/L when perfused with 10 and 15 min (P<0.05) , but this increase disappeared over time. LDH in cardiac perfusate increased as the MEHP given a higher concentration (P<0.05) . Compared with the control group, Histopathological analysis showed edema of myocardial tissue and cells, and inflammatory cells infiltration and myocardial cells necrosis were obvious in the MEHP perfusion groups. Myocardial ROS levels of the four MEHP treatment groups were all significantly higher than that of control group (P<0.05) . These heart damage induced by MEHP could be attenuated by NAC in different degrees. Conclusion MEHP can induce damage to myocardial tissue of isolated rat heart and one possible mechanism is the oxidative stress