L-NAME aggravates pulmonary oxygen toxicity in rats
| Autor: | J. Regnard, F Barale, J.P. Kantelip, Luc Rochette, Gilles Capellier, A. Boillot, Véronique Maupoil |
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| Rok vydání: | 1996 |
| Předmět: |
Male
Pulmonary and Respiratory Medicine medicine.medical_specialty Time Factors chemistry.chemical_element Lung injury Thiobarbituric Acid Reactive Substances Oxygen Nitric oxide Rats Sprague-Dawley chemistry.chemical_compound Internal medicine TBARS medicine Animals Enzyme Inhibitors Lung Oxygen toxicity Hyperoxia Respiratory Distress Syndrome medicine.diagnostic_test business.industry medicine.disease Rats NG-Nitroarginine Methyl Ester Bronchoalveolar lavage Endocrinology chemistry Immunology Toxicity Nitric Oxide Synthase medicine.symptom business Bronchoalveolar Lavage Fluid |
| Zdroj: | European Respiratory Journal. 9:2531-2536 |
| ISSN: | 1399-3003 0903-1936 |
| DOI: | 10.1183/09031936.96.09122531 |
| Popis: | Exposure to high oxygen concentration leads to acute lung injury and death in rats after 72 h. The pathophysiology of this phenomenon relies on several mechanisms, including alteration of vascular reactivity, recruitment and activation of neutrophils and alveolar macrophages, production of cytokines and excess production of free radicals. In addition to its potent vasodilating effect, nitric oxide (NO) has also been reported to prevent free radical-mediated damage. We wanted to determine whether NG-nitro-L-arginine methyl ester (L-NAME), a NO synthase inhibitor, might modulate oxygen toxicity. In rats exposed to continuous high oxygen concentration, we studied the effect of administration of 50 mg.kg-1 of intraperitoneal L-NAME twice a day on the first day of oxygen exposure. L-NAME resulted in earlier death, since 57% of the animals exposed to oxygen and injected with L-NAME died within 60 h as compared to 22% of the animals exposed to oxygen and treated with saline (p < 0.01). Haematocrit and bronchoalveolar lavage fluid protein were also significantly increased in animals exposed to oxygen and receiving L-NAME. The lung water content was higher in the oxygen-exposed groups (p < 0.01) and slightly decreased by L-NAME (p < 0.05). Thiobarbituaric acid reactive substances (TBARS) were elevated in plasma (p < 0.01) and decreased in lung (p < 0.001) of oxygen-exposed animals, but no significant effect of L-NAME was observed. NG-nitro-L-arginine methyl ester had a deleterious effect in rats exposed to hyperoxia, which might suggest that endogenous nitric oxide has a protective role against hyperoxia-induced pulmonary lesions. |
| Databáze: | OpenAIRE |
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