Kir6.2 is required for adaptation to stress
AUTOR(ES)
Zingman, Leonid V.
FONTE
The National Academy of Sciences
RESUMO
Reaction to stress requires feedback adaptation of cellular functions to secure a response without distress, but the molecular order of this process is only partially understood. Here, we report a previously unrecognized regulatory element in the general adaptation syndrome. Kir6.2, the ion-conducting subunit of the metabolically responsive ATP-sensitive potassium (KATP) channel, was mandatory for optimal adaptation capacity under stress. Genetic deletion of Kir6.2 disrupted KATP channel-dependent adjustment of membrane excitability and calcium handling, compromising the enhancement of cardiac performance driven by sympathetic stimulation, a key mediator of the adaptation response. In the absence of Kir6.2, vigorous sympathetic challenge caused arrhythmia and sudden death, preventable by calcium-channel blockade. Thus, this vital function identifies a physiological role for KATP channels in the heart.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=130624Documentos Relacionados
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