adrenomedullin and Burns

Clinical and experimental research findings suggest that a local burn insult produces oxidant-induced organ changes as evidenced by increased lipid peroxidation in lung, liver and gut. Adrenomedullin (AM), a potent vasodilator, was originally isolated from pheochromocytoma cells, and has been identified in other tissues. In this study, we investigated the potential role of AM in burn-induced remote organ damage in rats. Sprague-Dawley rats (250-300 g) were treated with either AM (100 ng/kg, subcutaneously) or saline 10 min before burn insult which covers 30% of total body surface area and were decapitated 24 h after the burn insult. Trunk blood was collected and analyzed for liver and kidney functions and for determination of TNF-alpha levels. The liver, lung and kidney samples were taken for histologic evaluation and for measurement of malondialdehyde (MDA) level, myeloperoxidase (MPO) activity and chemiluminescence levels. The data revealed that AM treatment resulted in a significant protection in tissues tested against burn injury via suppression of lipid peroxidation, tissue neutrophil infiltration, oxidant generation and via decreasing circulating levels of the pro-inflammatory cytokine TNF-alpha. AM treatment was also effective in attenuating hepatic and kidney dysfunction due to burn injury, suggesting that peripherally AM administration may protect the tissues against burn-induced injury.

Topics: Adrenomedullin; Animals; Burns; Disease Models, Animal; Kidney; Liver; Lung; Malondialdehyde; Peroxidase; Rats; Rats, Sprague-Dawley; Tumor Necrosis Factor-alpha

To observe the change in the plasma contents of adrenomedullin (ADM) and endothelin (ET) in burn patients, so as for us to explore their roles in the pathogenesis in the physiological disturbance in burn patients.. The plasma concentrations of ADM and ET were determined at 6, 12, 24 and 48 postburn hours (PBHs) in 40 burn patients with radioimmunoassay (RIA) and compared with those of 25 healthy people.. The postburn plasma levels of ADM and ET in burn patients increased immediately after injury, and they were positively correlated to burn area. The plasma ADM reached peak level at 12 PBHs and decreased thereafter, but remained at higher level than that in healthy people at 48 PBHs (P < 0.01). Plasma ET increased to top level at 6 PBH and decreased thereafter. But it remained at high level at 48 PBHs in severe burn patients (burned area larger than 45% TBSA) (P < 0.05 approximately 0.01). The plasma levels of ET and ADM increased proportionally and their ratio was close to that in normal control, but it decreased obviously after 6 PBH in all groups (P < 0.01).. There were evident postburn changes in plasma ADM and ET contents, and the results implied that ADM and ET played some roles in the development of postburn physiological disturbance.

Topics: Adolescent; Adrenomedullin; Adult; Burns; Child; Child, Preschool; Endothelins; Female; Humans; Male; Middle Aged; Peptides; Time Factors