[The influence of changes in the levels of calcitonin gene-related peptide and neuropeptide Y on cardiac function of severe burn patients during shock stage].

OBJECTIVE: To investigate the influence of the changes in the levels of calcitonin gene-related peptide (CGRP) and neuropeptide Y (NPY) on cardiac function of severe burn patients during shock stage. METHODS: Sixty severe burn patients with total burn surface area larger than 30% were enrolled as experiment group (E group) , and they received fluid resuscitation and debridement during shock stage. Sixty healthy volunteers were enrolled as control group (C group). The changes in the plasma level of CGRP, NPY and cTnT in E and C groups were observed at 1, 3, 6, 12, 24, 48 post-burn hours (PBH). The correlation among the CGRP, NPY and cTnT in the C group were analyzed. RESULTS: At 3 PBH, the plasma level of CGRP in E group (28 +/- 6) ng/L was lower than that in C group (55 +/- 7) ng/L , and it reached the lowest level at 12 PBH (15 +/- 4)ng/L . It was still lower than that in C group at 48 PBH (P < 0.05). The levels of NPY and cTnT in E group were significantly increased at 1PBH [(136 +/- 20) ng/L, (0.41 +/- 0.08) microg/L] compared with that in C group[ (86 +/- 13) ng/L, (0.16 +/- 0.06) microg/L], peaking at 12PBH [(189 +/- 31) ng/L, (1.78 +/- 0. 47) microg/L], and remaining higher than those in C group at 48PBH. There exhibited obvious negative correlation between the changes in the level of CGRP and cTnT ( r = -0.76, P < 0.01), while obvious positive correlation was found between the changes in level of NPY and cTnT ( r = 0.79, P < 0.01). CONCLUSION: The decrease in CGRP level and the increase in NPY level might play important roles in myocardial injury during shock stage of severe burn patients.

p38 mitogen-activated protein kinase inhibition attenuates burn-induced liver injury in rats.

This study was made to evaluate the effect of SB203580, a specific p38 MAP kinase inhibitor, on burn-induced hepatic injury as well as the activation of nuclear factor (NF)-kappaB in severely burned rats. Sprague-Dawley rats were divided into three groups: (1) sham group, rats underwent sham burn; (2) burn group, rats given third-degree burns over 30% total body surface area (TBSA) and treated with vehicle plus lactated Ringer solution for resuscitation 4 ml/(kg% TBSA); and (3) burn plus SB203580 group, rats given burn injury and fluid resuscitation plus SB203580 (10 mg/kg i.v., 15 min and 12 h after burn). Hepatocellular injury (measured by serum levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT)) and hepatocellular function (determined by the indocyanine green dye retention rate (ICG R15)) were assessed at 24 h post-burn. Liver histologic changes were also analyzed. Burn trauma resulted in increased serum aminotransferases concentrations, decreased ICG R15, elevated serum tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta levels and hepatic TNF-alpha and IL-1beta mRNA expressions, and worsen histologic condition. The level of Nuclear Factor (kappa) inhibitor (IkappaBalpha) in liver was decreased and DNA-binding activity of Nuclear Factor-kappaB (NF-kappaB) was increased after thermal injury. p38 MAP kinase was more significantly activated in liver harvested from burn rats than from shams. SB203580 inhibited the activation of p38 MAP kinase, reduced the levels of TNF-alpha and IL-1beta, and prevented burn-mediated liver injury. Both the IkappaBalpha level and NF-kappaB activity in the liver following burns was not affected by administration with SB203580. These findings suggest that (1) p38 MAP kinase activation is one important aspect of the signaling event that may mediate the release of TNF-alpha and IL-1beta and contributes to burn-induced liver injury and (2) p38 MAP kinase does not influence the activation of NF-kappaB directly in the liver of severely burned rats.