Referenced in: none

Automatically associated channels: BKβ , Slo1

Title: Large conductance, Ca2+-activated K+ channels (BKCa) and arteriolar myogenic signaling.

Authors: Michael A Hill, Yan Yang, Srikanth R Ella, Michael J Davis, Andrew P Braun

Journal, date & volume: FEBS Lett., 2010 May 17 , 584, 2033-42

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/20178789

Abstract
Myogenic, or pressure-induced, vasoconstriction is critical for local blood flow autoregulation. Underlying this vascular smooth muscle (VSM) response are events including membrane depolarization, Ca(2+) entry and mobilization, and activation of contractile proteins. Large conductance, Ca(2+)-activated K(+) channel (BK(Ca)) has been implicated in several of these steps including, (1) channel closure causing membrane depolarization, and (2) channel opening causing hyperpolarization to oppose excessive pressure-induced vasoconstriction. As multiple mechanisms regulate BK(Ca) activity (subunit composition, membrane potential (Em) and Ca(2+) levels, post-translational modification) tissue level diversity is predicted. Importantly, heterogeneity in BK(Ca) channel activity may contribute to tissue-specific differences in regulation of myogenic vasoconstriction, allowing local hemodynamics to be matched to metabolic requirements. Knowledge of such variability will be important to exploiting the BK(Ca) channel as a therapeutic target and understanding systemic effects of its pharmacological manipulation.