Document Detail

Antioxidants attenuate chronic hypoxic pulmonary hypertension.
MedLine Citation:
PMID:  9821844     Owner:  NLM     Status:  MEDLINE    
Because chronic hypoxia increases the production of oxygen radicals, we hypothesized that antioxidants attenuate chronic hypoxic pulmonary hypertension. In part 1, we examined the temporal progress in chronic hypoxic pulmonary hypertension in 46 Wistar rats exposed to hypoxia from 0-3 weeks. In part 2, we tested whether antioxidants attenuated chronic hypoxic pulmonary hypertension in 82 rats divided into 10 groups: control, fullerenol-1, U-83836E, dimethylthiourea-1, dimethylthiourea-2, hypoxia, hypoxia + fullerenol-1, hypoxia + U83836E, hypoxia + dimethylthiourea-1, and hypoxia + dimethylthiourea-2. Control animals breathed room air and were injected intraperitoneally with saline for 2 weeks. Fullerenol-1, U-83836E, and dimethylthiourea are antioxidants and were administered intraperitoneally for 2 weeks, except that dimethylthiourea was given either on days 3, 5, and 7 (dimethylthiourea-1), or on days 8, 10, and 12 (dimethylthiourea-2). Hypoxic animals were placed into a hypobaric chamber with a barometric pressure of 380 Torr for 2 weeks. Hypoxia + antioxidant groups were administered antioxidants during hypoxic exposure. We observed a gradual increase in pulmonary artery pressure, the weight ratio of right ventricle to left ventricle plus septum, and hematocrit during the 3 weeks of chronic hypoxia. These hypoxia-induced alterations were significantly attenuated by U-83836E and dimethylthiourea, but not by fullerenol-1. Neither the temporal alterations nor the antioxidant effects can be explained by the change in either tracheal neutral endopeptidase activity or the lung or plasma substance P level, perhaps because of the time lag in sampling. These results indicate that oxygen radicals play an important role in the development of chronic hypoxic pulmonary hypertension.
Y L Lai; H D Wu; C F Chen
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Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Journal of cardiovascular pharmacology     Volume:  32     ISSN:  0160-2446     ISO Abbreviation:  J. Cardiovasc. Pharmacol.     Publication Date:  1998 Nov 
Date Detail:
Created Date:  1999-01-08     Completed Date:  1999-01-08     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  7902492     Medline TA:  J Cardiovasc Pharmacol     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  714-20     Citation Subset:  IM    
Department of Physiology, College of Medicine, National Taiwan University, Taipei.
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MeSH Terms
Anoxia / complications*
Antioxidants / therapeutic use*
Body Weight / drug effects
Chronic Disease
Free Radicals
Hypertension, Pulmonary / drug therapy*,  etiology,  metabolism
Rats, Wistar
Substance P / physiology
Thiourea / analogs & derivatives,  pharmacology
Reg. No./Substance:
0/Antioxidants; 0/Free Radicals; 33507-63-0/Substance P; 61805-96-7/1,3-dimethylthiourea; 62-56-6/Thiourea

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