Abstract | OBJECTIVE: METHODS: Anesthetized rats were randomized to sham (control) or shock and clamp (s+c) groups. Animals in the s+c group underwent 1 hour of hemorrhagic shock (mean arterial blood pressure < or =50 mm Hg), followed by 45 minutes of supramesenteric aortic clamping, then 2 hours of resuscitated reperfusion. Animals in the s+c group were randomized to receive an intravenous bolus of C5aR antagonist at 1 mg/kg or saline solution control at the end of hemorrhagic shock. Intestinal and pulmonary permeability to iodine 125-labeled albumin was measured as an indicator of microvascular permeability. Tissue myeloperoxidase activity, proinflammatory cytokine tissue necrosis factor-alpha ( TNF-alpha) protein and mRNA, and C5aR mRNA levels were measured as indicators of neutrophil sequestration and inflammatory signaling, respectively. RESULTS: Lung permeability index was significantly increased in the s+c group compared with the sham group (4.43 +/- 0.96 vs 1.30 +/- 0.17; P <.01), and prevented with treatment with C5aR antagonist (1.74 +/- 0.50; P <.03). Lung myeloperoxidase activity was significantly increased in the the s+c group compared with the sham group (2.41 +/- 0.34 U/mg vs 1.03 +/- 0.29 U/mg; P <.009), and significantly attenuated with treatment with C5aR antagonist (1.11 +/- 0.09 U/mg; P <.006). Lung TNF-alpha protein levels were significantly elevated in both s+c groups, whereas lung TNF-alpha mRNA expression was significantly downregulated in both s+c groups compared with the sham group. Intestinal permeability index was significantly increased in animals in the s+c groups during reperfusion, compared with sham (P <.001), which was attenuated in early reperfusion with treatment with C5a receptor antagonist. Data represent mean +/- SEM, group comparisons with analysis of variance and post hoc Scheffé test. CONCLUSIONS: These results indicate that a potent antagonist of C5a receptor protects the rat intestine and lung from neutrophil-associated injury in a model of AAA rupture. These data suggest that complement-mediated inflammation can be modulated at the C5a receptor level, independent of proinflammatory TNF-alpha production, and prevent acute local and remote organ injury.
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Authors | Denis W Harkin, Alex Romaschin, Stephen M Taylor, Barry B Rubin, Thomas F Lindsay |
Journal | Journal of vascular surgery
(J Vasc Surg)
Vol. 39
Issue 1
Pg. 196-206
(Jan 2004)
ISSN: 0741-5214 [Print] United States |
PMID | 14718840
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Peptides, Cyclic
- Tumor Necrosis Factor-alpha
- complement C5a-inhibitors
- phenylalanyl(ornithinyl-prolyl-cyclohexylalanyl-tryptophyl-arginyl)
- Peroxidase
- Serine Endopeptidases
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Topics |
- Animals
- Aortic Aneurysm, Abdominal
(complications, physiopathology)
- Aortic Rupture
(complications, immunology, physiopathology)
- Capillary Permeability
- Complement Activation
- Complement Hemolytic Activity Assay
- Intestines
(physiopathology)
- Lung
(blood supply, metabolism)
- Male
- Multiple Organ Failure
(etiology, physiopathology, prevention & control)
- Peptides, Cyclic
(therapeutic use)
- Permeability
- Peroxidase
(analysis)
- Rats
- Rats, Sprague-Dawley
- Serine Endopeptidases
(therapeutic use)
- Tumor Necrosis Factor-alpha
(analysis)
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