Hypoxia and inflammation.

摘要

MAMMALS HAVE OXYGEN-SENSING MECHANISMS THAT HELP THEM adapt quickly to hypoxia by increasing respiration, blood flow, and survival responses. If an inadequate supply of oxygen persists, additional mechanisms attempt to restore oxygenation or help the body adapt to hypoxia. These other mechanisms rely on oxygen-sensing prolyl hydroxylases (PHDs), which hydrox-ylate prolines in the alpha subunit of the hypoxia-inducible transcription factor (HIP). This transcription factor is a heterodimer with two subunits: HIF-la or HIF-2a and HIF-1beta (or aryl hydrocarbon receptor nuclear translocator [ARNT] protein). HIF-la is ubiquitous, whereas HIF-2alpha is restricted to certain tissues.