Endogenous erythropoietin level and effects of exogenous erythropoietin in a rat model of blunt chest trauma-induced pulmonary contusion.
BACKGROUND
The present objective was to investigate endogen erythropoietin (EPO) level and relationship to oxidative stress within the first 24 hours of blunt chest trauma-induced pulmo-nary contusion (PCn) in a rat model.


METHODS
Thirty-five rats were divided into 3 groups. In the baseline control group (BC, n=7), rats were uninjured and untreated. In the positive control group (PC, n=21) rats were injured but untreated. In the EPO-24 group (n=7), rats were injured and a single dose of intra-peritoneal EPO (5000 IU/kg) was administered immediately after lung injury. The PC group was divided into 3 subgroups: PC-6 (n=7), PC-12 (n=7), and PC-24 (n=7). The BC group was subjected to thoracotomy, and the right lung was harvested. The PC subgroups were eu-thanized at 6, 12, and 24 hours after injury, respectively. The EPO-24 group was euthanized at the 24th hour after injury. Lung samples were obtained, levels of malondialdehyde (MDA) and EPO were analyzed, and activities of superoxide dismutase (SOD) and catalase (CAT) were then measured in homogenized lung tissue samples. Histologic damage to lung tissue in the BC group, the EPO-24 group, and PC subgroup euthanized at the 24th hour after injury were scored by a single pathologist blinded to group assignation.


RESULTS
Mean MDA levels, as well as SOD and CAT activities, of the BC and EPO-24 groups were significantly lower than those of the PC group (p<0.005). Mean EPO concentra-tion of the PC group was significantly higher than that of the BC group (p<0.005). Lung tis-sue damage scores measured at 24 hours after injury were significantly lower in the EPO-24 group than in the PC group (p<0.005).


CONCLUSIONS
In the present PCn rat model, EPO concentrations, as well as SOD and CAT levels, were high in lung tissue, when measured at 24 hours after PCn. When administered early after chest trauma, EPO significantly attenuated oxidative damage and tissue damage in the early phase, as assessed by biochemical markers and histologic scoring.
Department of Pediatric Surgery, Esenler Women and Children Diseases Hospital, İstanbul-Turkey. vbakan@gmail.com.
Vedat
V
Bakan
Department of Biochemistry, Sütçü İmam University Faculty of Medicine, Kahramanmaraş-Turkey.
Ergül Belge
EB
Kurutaş
Department of Pathology, Sütçü İmam University Faculty of Medicine, Kahramanmaraş-Turkey.
Harun
H
Çıralık
Department of Microbiology, Sütçü İmam University Faculty of Medicine, Kahramanmaraş-Turkey.
Mustafa
M
Gül
Department of Biochemistry, Sütçü İmam University Faculty of Medicine, Kahramanmaraş-Turkey.
Ahmet
A
Çelik
D000818:Animals; D003288:Contusions / Q000097:blood / Q000188:drug therapy; D004195:Disease Models, Animal; D004921:Erythropoietin / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D007263:Infusions, Parenteral; D008168:Lung / Q000187:drug effects*; D055370:Lung Injury / Q000097:blood / Q000188:drug therapy*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D014949:Wounds, Nonpenetrating / Q000097:blood / Q000188:drug therapy*
D004921:Erythropoietin