期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2002
卷号：99
期号：2
页码：821-826
DOI：10.1073/pnas.022634199
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：To investigate whether the transcriptional activator hypoxia-inducible factor 1 (HIF-1) is required for ventilatory responses to hypoxia, we analyzed mice that were either wild type or heterozygous for a loss-of-function (knockout) allele at the Hif1a locus, which encodes the O2-regulated HIF-1 subunit. Although the ventilatory response to acute hypoxia was not impaired in Hif1a+/- mice, the response was primarily mediated via vagal afferents, whereas in wild-type mice, carotid body chemoreceptors played a predominant role. When carotid bodies isolated from wild-type mice were exposed to either cyanide or hypoxia, a marked increase in sinus nerve activity was recorded, whereas carotid bodies from Hif1a+/- mice responded to cyanide but not to hypoxia. Histologic analysis revealed no abnormalities of carotid body morphology in Hif1a+/- mice. Wild-type mice exposed to hypoxia for 3 days manifested an augmented ventilatory response to a subsequent acute hypoxic challenge. In contrast, prior chronic hypoxia resulted in a diminished ventilatory response to acute hypoxia in Hif1a+/- mice. Thus partial HIF-1 deficiency has a dramatic effect on carotid body neural activity and ventilatory adaptation to chronic hypoxia.
