Effects of therapeutic hypercapnia on inflammation and apoptosis after hepatic ischemia-reperfusion injury in rats.
BACKGROUND
Therapeutic hypercapnia (TH) has been demonstrated to protect several organs ischemia-reperfusion injury. The study aimed to investigate the effects of therapeutic hypercapnia on hepatic ischemia-reperfusion injury (HIRI).


METHODS
Thirty adult male Wistar rats weighing (250+/-20) g were randomized into 3 groups (n=10 in each), group C (control group), group A (hypercapnia group) and group B (CO2 preconditioning group). A segmental ischemia of the liver was induced by interrupting the blood vessels including the bile duct to the median and left lateral lobes for 60 minutes and all the animals were sacrificed after 240 minutes observation period of reperfusion. Mean arterial pressure (MAP) and the blood gases were measured before ischemia (baseline) and at 30, 60, 120, 180 and 240 minutes after reperfusion. Arterial blood samples were obtained for determination of serum levels of TNF-alpha, IL-10, serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT). The histopathology of liver tissues was evaluated by light microscopy. The NF-kappaB expression and apoptotic hepatocytes were respectively determined by immunohistochemistry and TUNEL assay.


RESULTS
The serum levels of liver enzymes and TNF-alpha were significantly decreased while the IL-10 level was significantly increased in groups A and B than in group C (P<0.05), and group B surpassed group A (P<0.05). The histopathological scores, the NF-kappaB immunohistochemical score (IHS) and apoptotic index were significantly lower in groups A and B than in group C (P<0.05), and the decrease in group B was more obvious than in group A (P<0.05).


CONCLUSIONS
Therapeutic hypercapnia attenuates ischemia-reperfusion injury to the liver. Moreover, the effects of CO2 preconditioning are outstandingly notable.
Li
Ai-min
AM
Department of Anesthesiology, second Affiliated Hospital, Harbin Medical University, Harbin, Heilongjiang 150086, China.
Quan
Yan
Y
Guo
Yue-ping
YP
Li
Wen-zhi
WZ
Cui
Xiao-guang
XG
D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D002245:Carbon Dioxide / Q000627:therapeutic use*; D006439:Hemodynamics / Q000187:drug effects; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D007249:Inflammation / Q000188:drug therapy / Q000378:metabolism; D016753:Interleukin-10 / Q000097:blood; D008099:Liver / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology*; D008297:Male; D016328:NF-kappa B / Q000378:metabolism; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000097:blood / Q000188:drug therapy* / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000097:blood
D016328:NF-kappa B; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10; D002245:Carbon Dioxide