• Nanion Technologies: Smart Tools for Ion Channel Research

    Nanion Technologies: Smart Tools for Ion Channel Research

  • SyncroPatch 384i: HTS Automated Patch Clamp

    SyncroPatch 384i: HTS Automated Patch Clamp

  • SURFE²R 96SE: Label-free HTS Transporter Screening

    SURFE²R 96SE: Label-free HTS Transporter Screening

  • Dynamic Clamp: Patchliner

    Dynamic Clamp: Patchliner

  • Bilayer recordings: Orbit product family

    Bilayer recordings: Orbit product family

  • CardioExcyte 96 SOL: Pacing Cardiomyocytes with Light

    CardioExcyte 96 SOL: Pacing Cardiomyocytes with Light

Our Product Portfolio

SyncroPatch 384i

SyncroPatch 384i

Patchliner

Patchliner

Port-a-Patch

Port-a-Patch

Port-a-Patch mini

Port-a-Patch mini

CardioExcyte 96

CardioExcyte 96

FLEXcyte 96

FLEXcyte 96

SURFE²R 96SE

SURFE²R 96SE

SURFE²R N1

SURFE²R N1

Orbit 16

Orbit 16

Orbit Mini

Orbit Mini

Vesicle Prep Pro

Vesicle Prep Pro

2014 - KCNMA1 Encoded Cardiac BK Channels Afford Protection against Ischemia-Reperfusion Injury

icon pap  Port-a-Patch publication in PLoS One (2014)

Authors: 
Soltysinska E., Bentzen B.H., Barthmes M., Hattel H., Thrush A.B., Harper M.E., Qvortrup K., Larsen F.J., Schiffer T.A., Losa-Reyna J., Straubinger J., Kniess A., Thomsen M.B., Brüggemann A., Fenske S., Biel M., Ruth P., Wahl-Schott C., Boushel R.C., Olesen S.P., Lukowski R.

 

Journal: 
PLoS One (2014) 9(7):e103402


Abstract: 

Mitochondrial potassium channels have been implicated in myocardial protection mediated through pre-/postconditioning. Compounds that open the Ca2+- and voltage-activated potassium channel of big-conductance (BK) have a pre-conditioning-like effect on survival of cardiomyocytes after ischemia/reperfusion injury. Recently, mitochondrial BK channels (mitoBKs) in cardiomyocytes were implicated as infarct-limiting factors that derive directly from the KCNMA1 gene encoding for canonical BKs usually present at the plasma membrane of cells. However, some studies challenged these cardio-protective roles of mitoBKs. Herein, we present electrophysiological evidence for paxilline- and NS11021-sensitive BK-mediated currents of 190 pS conductance in mitoplasts from wild-type but not BK−/− cardiomyocytes. Transmission electron microscopy of BK−/− ventricular muscles fibres showed normal ultra-structures and matrix dimension, but oxidative phosphorylation capacities at normoxia and upon re-oxygenation after anoxia were significantly attenuated in BK−/− permeabilized cardiomyocytes. In the absence of BK, post-anoxic reactive oxygen species (ROS) production from cardiomyocyte mitochondria was elevated indicating that mitoBK fine-tune the oxidative state at hypoxia and re-oxygenation. Because ROS and the capacity of the myocardium for oxidative metabolism are important determinants of cellular survival, we tested BK−/− hearts for their response in an ex-vivo model of ischemia/reperfusion (I/R) injury. Infarct areas, coronary flow and heart rates were not different between wild-type and BK−/− hearts upon I/R injury in the absence of ischemic pre-conditioning (IP), but differed upon IP. While the area of infarction comprised 28±3% of the area at risk in wild-type, it was increased to 58±5% in BK−/− hearts suggesting that BK mediates the beneficial effects of IP. These findings suggest that cardiac BK channels are important for proper oxidative energy supply of cardiomyocytes at normoxia and upon re-oxygenation after prolonged anoxia and that IP might indeed favor survival of the myocardium upon I/R injury in a BK-dependent mode stemming from both mitochondrial post-anoxic ROS modulation and non-mitochondrial localizations.


Download here

Back to Overview

Nanion Corporate Blog

We use cookies on our website. Some of them are essential for the operation of the site, while others help us to improve this site and the user experience (tracking cookies). You can decide for yourself whether you want to allow cookies or not. Please note that if you reject them, you may not be able to use all the functionalities of the site.