Interaction of hypoxia and core temperature: potential role of TRPV1.
Hypoxia exposure in small mammals elicits an initial rise in ventilation followed by a reduction to levels that are often less than the normoxic value. The fall in ventilation is matched by a decrease in metabolism rate and a reduction in core body temperature (Tb). The transient receptor potential vanilloid 1 (TRPV1) ion channel has been implicated in thermoregulation (Caterina et al., Science 288:306-313, 2000) and recently shown to exert a tonic effect on Tb in human subjects (Gavva et al., Pain 136:202-210, 2008). We review herein the hypothesis that TRPV1 modulates the Tb response to hypoxia. We provide preliminary evidence that a 24 h hypoxia (FIO(2)=0.1) exposure caused an enhanced decrease in Tb in mutant TRPV1(-/-) mice compared to the TRPV1(+/+) genotype (Tb was » 1°C lower than TRPV1(+/+)). Further investigation is warranted to determine the extent of TRPV1 ion channel involvement in acute and adaptive responses to hypoxia.
Department of Biomedical and Molecular Sciences, Queen's University, Ontario, Kingston, Canada.
Nathaniel Y W
NY
Yuen
Sandra G
SG
Vincent
Brian
B
Foo
John T
JT
Fisher
D000222:Adaptation, Physiological; D000818:Animals; D001833:Body Temperature Regulation / Q000502:physiology*; D006801:Humans; D000860:Hypoxia / Q000503:physiopathology*; D051379:Mice; D050916:TRPV Cation Channels / Q000502:physiology*
D050916:TRPV Cation Channels; C494484:TRPV1 receptor