Abstract | BACKGROUND: DESIGN: Controlled, block-randomized study. SETTING: University research laboratory. SUBJECT: Mixed breed piglets (1-4d, 1.6-2.4 kg). INTERVENTIONS: Acutely instrumented piglets received normocapnic alveolar hypoxia (10-15% oxygen) for 2 h followed by reoxygenation with 100% oxygen (1 h) then 21% oxygen (3 h). After reoxygenation, hypoxic-reoxygenated piglets were given either saline (controls), NAC [30 mg/kg bolus + 20 mg/(kg h) infusion], NMMA [0.1 mg/kg bolus + 0.1 mg/(kg h) infusion] or NAC + L-NMMA via intravenous infusion in a blinded, randomized fashion (n = 8/group). Sham-operated piglets had no hypoxia-reoxygenation (n = 5). MEASUREMENTS AND RESULTS: Both cardiac index and stroke volume of hypoxia-reoxygenation controls remained depressed during reoxygenation (vs. normoxic baseline, p < 0.05). Post- resuscitation treatment with L-NMMA alone did not improve systemic hemodynamic recovery, but caused pulmonary hypertension (vs. controls). In contrast, treating the piglets with either NAC or NAC + L-NMMA improved cardiac index and stroke volume, with no effect on heart rate and blood pressure (vs. controls). These treatments also decreased various oxidative stress markers in myocardial tissues (vs. controls). However, there was no significant difference between NAC- and NAC + L-NMMA groups in all examined parameters. CONCLUSIONS: Post- resuscitation administration of NAC improved cardiac function and reduced oxidative stress in newborn pigs with hypoxia-reoxygenation insult. Low-dose, non-selective inhibitor of nitric oxide synthase activity did not provide any further beneficial effect.
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Authors | Tze-fun Lee, Corinne N Tymafichuk, Richard Schulz, Po-Yin Cheung |
Journal | Intensive care medicine
(Intensive Care Med)
Vol. 35
Issue 9
Pg. 1628-35
(Sep 2009)
ISSN: 1432-1238 [Electronic] United States |
PMID | 19551371
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Antioxidants
- Nitric Oxide
- Acetylcysteine
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Topics |
- Acetylcysteine
(administration & dosage)
- Alberta
- Animals
- Antioxidants
- Blood Gas Analysis
- Hemodynamics
(drug effects)
- Hypoxia
- Nitric Oxide
(administration & dosage, pharmacology, therapeutic use)
- Random Allocation
- Resuscitation
- Stroke Volume
(physiology)
- Swine
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