Gene transcription of brain voltage-gated potassium channels is reversibly regulated by oxygen supply.
Voltage-dependent potassium channels (Kv channels) are important determinants of brain electrical activity. Hypoxia may be an important modifier, because several voltage-gated K+ channels are reversibly blocked by acute hypoxia and are thought to act as oxygen sensors. Here we show, using the anoxia-tolerant turtle brain (Trachemys scripta) as a model, that brain Kv1 channel transcription is reversibly regulated by oxygen supply. We found that in turtle brains exposed to 4-h anoxia Kv1 transcripts were reduced to 18.5% of normoxic levels. Kv1 channel mRNA levels were restored to normal within 4 h of subsequent reoxygenation. Our results provide clear evidence that brain Kv channel expression is sensitive to oxygen supply and indicate an important mechanism that matches brain activity to oxygen supply.
Prentice
Howard M
HM
Department of Biomedical Sciences, Florida Atlantic University, Boca Raton 33431, USA. hprentic@fau.edu
Milton
Sarah L
SL
Scheurle
Daniela
D
Lutz
Peter L
PL
D000222:Adaptation, Physiological / Q000502:physiology; D000818:Animals; D001921:Brain / Q000502:physiology; D005786:Gene Expression Regulation / Q000502:physiology; D002534:Hypoxia, Brain / Q000503:physiopathology*; D010100:Oxygen / Q000502:physiology*; D024642:Potassium Channels, Voltage-Gated / Q000235:genetics*; D012333:RNA, Messenger / Q000378:metabolism; D014158:Transcription, Genetic / Q000502:physiology*; D014426:Turtles
D024642:Potassium Channels, Voltage-Gated; D012333:RNA, Messenger; D010100:Oxygen