Referenced in: none

Automatically associated channels: Kv2.1

Title: Hypoxia suppresses Kv 2.1 channel expression through endogenous 15-hydroxyeicosatetraenoic acid in rat pulmonary artery.

Authors: Lei Guo, Zhaoping Qiu, Lei Zhang, Shuo Chen, Daling Zhu

Journal, date & volume: J Physiol Sci, 2010 Sep , 60, 373-81

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/20680544

Abstract
We have previously reported that hypoxia activates lung 15-lipoxygenase (15-LOX), which catalyzes arachidonic acid to produce 15-HETE, leading to constriction of neonatal rabbit pulmonary arteries. Hypoxia suppresses Kv2.1 channel expression. Although the Kv channel inhibition by hypoxia is likely to be mediated through 15-HETE, direct evidence is still lacking. To explore whether 15-LOX/15-HETE pathway contributes to the hypoxia-induced down-regulation of Kv2.1 channel, we performed studies using 15-LOX blockers, semi-quantitative PCR and western blot analysis. We found that Kv2.1 channel expression at the mRNA and protein levels was greatly up-regulated in pulmonary arterial smooth muscle cells (PASMCs) and pulmonary artery (PA) after blockade of endogenous 15-HETE under hypoxic condition. 15-HETE further decreased Kv2.1 channel expression in comparison with 12-HETE and 5-HETE in cultured PASMCs and PA under normoxic conditions. These data indicate that hypoxia suppresses Kv2.1 channel expression through endogenous 15-HETE in PA.