Abstract
Exposure of rats to 10% O2 for 4 days caused pulmonary hypertension and induced expression of both inducible nitric oxide synthase (iNOS) and CCAAT box enhancer binding protein-β (C/EBP-β) in rat lung. Electrophoretic mobility shift assays (EMSAs) showed that exposure to 1% O2 increased the C/EBP-β binding in rat pulmonary microvascular smooth muscle cells (rPSMs). To test the hypothesis that C/EBP-β participates in hypoxia-induced iNOS expression in rPSMs, a C/EBP motif at -910 bp of rat iNOS promoter was mutated. rPSMs transfected with the rat iNOS promoter and exposed to 1% O2 for 24 hours had significantly increased wild-type iNOS promoter activity. The hypoxia-induced promoter activity was abolished by the C/EBP motif mutation. Thus, C/EBP-β mediates, at least in part, hypoxia-induced iNOS expression in rPSMs.
Original language | English (US) |
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Pages (from-to) | 125-127 |
Number of pages | 3 |
Journal | Circulation research |
Volume | 90 |
Issue number | 2 |
DOIs | |
State | Published - Feb 8 2002 |
Keywords
- C/EBP-β
- Gene regulation
- Hypoxia
- Inducible nitric oxide synthase
- Pulmonary hypertension
ASJC Scopus subject areas
- Physiology
- Cardiology and Cardiovascular Medicine