Format

Send to

Choose Destination
Proc Natl Acad Sci U S A. 2011 Feb 15;108(7):3065-70. doi: 10.1073/pnas.1100064108. Epub 2011 Jan 31.

Hypoxia-inducible factor 2α (HIF-2α) heterozygous-null mice exhibit exaggerated carotid body sensitivity to hypoxia, breathing instability, and hypertension.

Author information

1
Biological Sciences Division, Institute for Integrated Physiology and Center for Systems Biology of O2 Sensing, University of Chicago, Chicago, IL 60637, USA.

Abstract

Cardiorespiratory functions in mammals are exquisitely sensitive to changes in arterial O(2) levels. Hypoxia-inducible factors (e.g., HIF-1 and HIF-2) mediate transcriptional responses to reduced oxygen availability. We demonstrate that haploinsufficiency for the O(2)-regulated HIF-2α subunit results in augmented carotid body sensitivity to hypoxia, irregular breathing, apneas, hypertension, and elevated plasma norepinephrine levels in adult Hif-2α(+/-) mice. These dysregulated autonomic responses were associated with increased oxidative stress and decreased mitochondrial electron transport chain complex I activity in adrenal medullae as a result of decreased expression of major cytosolic and mitochondrial antioxidant enzymes. Systemic administration of a membrane-permeable antioxidant prevented oxidative stress, normalized hypoxic sensitivity of the carotid body, and restored autonomic functions in Hif-2α(+/-) mice. Thus, HIF-2α-dependent redox regulation is required for maintenance of carotid body function and cardiorespiratory homeostasis.

PMID:
21288809
PMCID:
PMC3041114
DOI:
10.1073/pnas.1100064108
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center