Unknown

Dataset Information

0

Endothelial SK(Ca) and IK(Ca) channels regulate brain parenchymal arteriolar diameter and cortical cerebral blood flow.


ABSTRACT: Calcium-sensitive potassium (K(Ca)) channels have been shown to modulate the diameter of cerebral pial arteries; however, little is known regarding their roles in controlling cerebral parenchymal arterioles (PAs). We explored the function and cellular distribution of small-conductance (SK(Ca)) and intermediate-conductance (IK(Ca)) K(Ca) channels and large-conductance K(Ca) (BK(Ca)) channels in endothelial cells (ECs) and smooth muscle cells (SMCs) of PAs. Both SK(Ca) and IK(Ca) channels conducted the outward current in isolated PA ECs (current densities, ~20?pA/pF and ~28?pA/pF at +40?mV, respectively), but these currents were not detected in PA SMCs. In contrast, BK(Ca) currents were prominent in PA SMCs (~154?pA/pF), but were undetectable in PA ECs. Pressurized PAs constricted to inhibition of SK(Ca) (~16%) and IK(Ca) (~16%) channels, but were only modestly affected by inhibition of BK(Ca) channels (~5%). Blockade of SK(Ca) and IK(Ca) channels decreased resting cortical cerebral blood flow (CBF) by ~15%. NS309 (6,7-dichloro-1H-indole-2,3-dione3-oxime), a SK(Ca)/IK(Ca) channel opener, hyperpolarized PA SMCs by ~27?mV, maximally dilated pressurized PAs, and increased CBF by ~40%. In conclusion, these data show that SK(Ca) and IK(Ca) channels in ECs profoundly modulate PA tone and CBF, whereas BK(Ca) channels in SMCs only modestly influence PA diameter.

SUBMITTER: Hannah RM 

PROVIDER: S-EPMC3099631 | biostudies-literature | 2011 May

REPOSITORIES: biostudies-literature

altmetric image

Publications

Endothelial SK(Ca) and IK(Ca) channels regulate brain parenchymal arteriolar diameter and cortical cerebral blood flow.

Hannah Rachael M RM   Dunn Kathryn M KM   Bonev Adrian D AD   Nelson Mark T MT  

Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism 20101222 5


Calcium-sensitive potassium (K(Ca)) channels have been shown to modulate the diameter of cerebral pial arteries; however, little is known regarding their roles in controlling cerebral parenchymal arterioles (PAs). We explored the function and cellular distribution of small-conductance (SK(Ca)) and intermediate-conductance (IK(Ca)) K(Ca) channels and large-conductance K(Ca) (BK(Ca)) channels in endothelial cells (ECs) and smooth muscle cells (SMCs) of PAs. Both SK(Ca) and IK(Ca) channels conducte  ...[more]

Similar Datasets

| S-EPMC1571984 | biostudies-literature
| S-EPMC3543990 | biostudies-literature
| S-EPMC7484264 | biostudies-literature
| S-EPMC3564200 | biostudies-literature
| S-EPMC1573921 | biostudies-literature
| S-EPMC3041654 | biostudies-literature
| S-EPMC6621142 | biostudies-literature
| S-EPMC4269733 | biostudies-literature
| S-EPMC6417832 | biostudies-literature
| S-EPMC2916930 | biostudies-literature