Chronic inhaled nitric oxide: effects on pulmonary vascular endothelial function and pathology in rats
| Autor: | Deborah U. Frank, Roger A. Johns, C. M. Roos, George F. Rich, Chun Xue |
|---|---|
| Rok vydání: | 1996 |
| Předmět: |
Male
medicine.medical_specialty Pulmonary Circulation Endothelium Physiology Vasodilation Blood Pressure Arginine Nitric Oxide Muscle Smooth Vascular Nitric oxide Rats Sprague-Dawley chemistry.chemical_compound Physiology (medical) Internal medicine Hypoxic pulmonary vasoconstriction Administration Inhalation medicine Animals Vasoconstrictor Agents Enzyme Inhibitors Hypoxia Air Pressure biology business.industry Angiotensin II Endothelium-derived relaxing factor Organ Size Hypoxia (medical) medicine.disease Pulmonary hypertension Rats Nitric oxide synthase Endocrinology medicine.anatomical_structure NG-Nitroarginine Methyl Ester chemistry Anesthesia biology.protein Ventricular Function Right Endothelium Vascular medicine.symptom Nitric Oxide Synthase business |
| Zdroj: | Journal of applied physiology (Bethesda, Md. : 1985). 80(1) |
| ISSN: | 8750-7587 |
| Popis: | Nitric oxide (NO) is a potent endogenous vasodilator produced in endothelial cells. Inhaled NO selectively vasodilates the pulmonary circulation. We determined the effects of chronic inhaled NO on hypoxic pulmonary vascular remodeling and endothelium NO-dependent and -independent vasodilation during normoxic and hypoxic conditions in rats. Rats were exposed to 3 wk of normoxia (N), normoxia + 20 ppm inhaled NO (N+NO), chronic hypoxia with 10% normobaric oxygen (CH), or CH and 20 ppm inhaled NO (CH+NO). Inhaled NO decreased the number of muscular pulmonary arteries, the medial smooth muscle thickness, and the right ventricular hypertrophy associated with chronic hypoxia but had no effect on these parameters in normoxic rats. All groups were evaluated with isolated perfused lungs. The pulmonary artery pressure increased by the same amount in the CH and CH+NO rats compared with N rats. Inhibition of NO synthase with N omega-nitro-L-arginine methyl ester (L-NAME) caused greater pulmonary vasoconstriction in CH (19.2 +/- 3.7 mmHg) vs. N (7.8 +/- 3.0 mmHg) and less in CH+NO (9.1 +/- 0.8 mmHg) vs. CH rats. Bradykinin (3 micrograms) caused greater vasodilation in CH (76 +/- 12%) vs. N (29 +/- 5%) but significantly less in CH+NO (41 +/- 11%) vs. CH rats. Vasodilation with acute inhaled NO (40 ppm) was no different in CH vs. N rats but was lower in CH+NO (19 +/- 5%) vs. CH (34 +/- 6%) rats. This study demonstrates that chronic inhaled NO attenuates hypoxic pulmonary vascular remodeling. Furthermore, these results suggest that chronic inhaled NO decreases endothelium NO-dependent and -independent vasodilation. |
| Databáze: | OpenAIRE |
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