Vladimir Matchkov

The NA+/K+-ATPase controls gap junctions via membrane microdomain interactions in rat smooth muscles.

Research output: Contribution to conferencePosterResearch

Standard

The NA+/K+-ATPase controls gap junctions via membrane microdomain interactions in rat smooth muscles.. / Matchkov, Vladimir; Nilsson, Holger; Aalkjær, Christian.

2008. Poster session presented at 12th International ATPase Conference - Na,K-ATPase and Related Transport ATPases of P-type: Structures, Mechanisms, and Roles in Health and Disease, Aarhus, Denmark.

Research output: Contribution to conferencePosterResearch

Harvard

Matchkov, V, Nilsson, H & Aalkjær, C 2008, 'The NA+/K+-ATPase controls gap junctions via membrane microdomain interactions in rat smooth muscles.', 12th International ATPase Conference - Na,K-ATPase and Related Transport ATPases of P-type: Structures, Mechanisms, and Roles in Health and Disease, Aarhus, Denmark, 05/08/2008 - 10/08/2008.

APA

Matchkov, V., Nilsson, H., & Aalkjær, C. (2008). The NA+/K+-ATPase controls gap junctions via membrane microdomain interactions in rat smooth muscles.. Poster session presented at 12th International ATPase Conference - Na,K-ATPase and Related Transport ATPases of P-type: Structures, Mechanisms, and Roles in Health and Disease, Aarhus, Denmark.

CBE

Matchkov V, Nilsson H, Aalkjær C. 2008. The NA+/K+-ATPase controls gap junctions via membrane microdomain interactions in rat smooth muscles. Poster session presented at 12th International ATPase Conference - Na,K-ATPase and Related Transport ATPases of P-type: Structures, Mechanisms, and Roles in Health and Disease, Aarhus, Denmark.

MLA

Matchkov, Vladimir, Holger Nilsson, and Christian Aalkjær The NA+/K+-ATPase controls gap junctions via membrane microdomain interactions in rat smooth muscles.. 12<sup>th</sup> International ATPase Conference - Na,K-ATPase and Related Transport ATPases of P-type: Structures, Mechanisms, and Roles in Health and Disease, 05 Aug 2008, Aarhus, Denmark, Poster, 2008. 1 p.

Vancouver

Matchkov V, Nilsson H, Aalkjær C. The NA+/K+-ATPase controls gap junctions via membrane microdomain interactions in rat smooth muscles.. 2008. Poster session presented at 12th International ATPase Conference - Na,K-ATPase and Related Transport ATPases of P-type: Structures, Mechanisms, and Roles in Health and Disease, Aarhus, Denmark.

Author

Matchkov, Vladimir ; Nilsson, Holger ; Aalkjær, Christian. / The NA+/K+-ATPase controls gap junctions via membrane microdomain interactions in rat smooth muscles. Poster session presented at 12th International ATPase Conference - Na,K-ATPase and Related Transport ATPases of P-type: Structures, Mechanisms, and Roles in Health and Disease, Aarhus, Denmark.1 p.

Bibtex

@conference{118daed0694911dd9251000ea68e967b,
title = "The NA+/K+-ATPase controls gap junctions via membrane microdomain interactions in rat smooth muscles.",
abstract = "The Na+/K+-ATPase is known to interact with many membrane and cytosolic proteins by organizing various signaling complexes. These interactions were suggested to be important in regulation of various cellular responses. Pumping activity of the Na+/K+-ATPase is suggested to be essential for some of these interactions, while other responses may be independent of pumping activity. The Na+/K+-pump differs from other P-type ATPases by its sensitivity to cardiotonic steroids such as ouabain. However, rodent tissues express both ouabain-insensitive (α1) and ouabain-sensitive (α2 and α3) isoforms of Na+/K+-ATPases. Based on our previous findings we hypothesized here that the ouabain-sensitive isoform of the Na+/K+-ATPase can regulate vascular tone by interaction with Na+/Ca2+-exchanger, gap junctions and KATP channels.[Ca2+]i in individual smooth muscle cells (SMCs) was imaged simultaneously with isometric force in rat mesenteric small arteries. Paired cultured rat smooth muscle cells (A7r5) were used as a model for electrical coupling of SMC by measuring membrane capacitance (Cm). PCR, Western blotting and immunohistochemistry were used to identify the membrane transporters. SMCs were uncoupled (evaluated by inhibition of vasomotion and desynchronization of [Ca2+]i transients in the vascular wall, or by reduction of Cm measured in paired A7r5 cells) when the Na+/K+-ATPase was inhibited either by a low concentration of ouabain (1-10 µM) or by ATP depletion. Inhibition of the Na+/Ca2+-exchange activity by SEA0400 or by lowering the extracellular Na+ concentration also uncoupled the cells. Reduction of Na+/K+-ATPase activity by removal of extracellular K+ uncoupled cells, but only after inhibition of KATP channels. This interaction was bidirectional. Depletion of [Na+]i and clamping [Ca2+]i at low levels prevented the uncoupling. Low ouabain concentration evoked spatially restricted [Ca2+]i transients along the cell periphery.All three isoforms of the Na+/K+-ATPase α subunit were found in SMCs but based on ouabain-sensitivity and co-precipitation experiments we suggest that α2 Na+/K+-ATPase subunit is involved in regulation of the intercellular communication.We have here shown that gap junctions between SMCs are regulated through an interaction between the Na+/K+-ATPase and the Na+/Ca2+-exchanger leading to an increase in [Ca2+]i in discrete areas near the plasma membrane. We have also suggested that this Na+/K+-pump-containing microdomain is functionally linked to KATP channels via the local ion homeostasis. ",
author = "Vladimir Matchkov and Holger Nilsson and Christian Aalkj{\ae}r",
note = "Sider: 178; null ; Conference date: 05-08-2008 Through 10-08-2008",
year = "2008",
language = "English",

}

RIS

TY - CONF

T1 - The NA+/K+-ATPase controls gap junctions via membrane microdomain interactions in rat smooth muscles.

AU - Matchkov, Vladimir

AU - Nilsson, Holger

AU - Aalkjær, Christian

N1 - Conference code: 12

PY - 2008

Y1 - 2008

N2 - The Na+/K+-ATPase is known to interact with many membrane and cytosolic proteins by organizing various signaling complexes. These interactions were suggested to be important in regulation of various cellular responses. Pumping activity of the Na+/K+-ATPase is suggested to be essential for some of these interactions, while other responses may be independent of pumping activity. The Na+/K+-pump differs from other P-type ATPases by its sensitivity to cardiotonic steroids such as ouabain. However, rodent tissues express both ouabain-insensitive (α1) and ouabain-sensitive (α2 and α3) isoforms of Na+/K+-ATPases. Based on our previous findings we hypothesized here that the ouabain-sensitive isoform of the Na+/K+-ATPase can regulate vascular tone by interaction with Na+/Ca2+-exchanger, gap junctions and KATP channels.[Ca2+]i in individual smooth muscle cells (SMCs) was imaged simultaneously with isometric force in rat mesenteric small arteries. Paired cultured rat smooth muscle cells (A7r5) were used as a model for electrical coupling of SMC by measuring membrane capacitance (Cm). PCR, Western blotting and immunohistochemistry were used to identify the membrane transporters. SMCs were uncoupled (evaluated by inhibition of vasomotion and desynchronization of [Ca2+]i transients in the vascular wall, or by reduction of Cm measured in paired A7r5 cells) when the Na+/K+-ATPase was inhibited either by a low concentration of ouabain (1-10 µM) or by ATP depletion. Inhibition of the Na+/Ca2+-exchange activity by SEA0400 or by lowering the extracellular Na+ concentration also uncoupled the cells. Reduction of Na+/K+-ATPase activity by removal of extracellular K+ uncoupled cells, but only after inhibition of KATP channels. This interaction was bidirectional. Depletion of [Na+]i and clamping [Ca2+]i at low levels prevented the uncoupling. Low ouabain concentration evoked spatially restricted [Ca2+]i transients along the cell periphery.All three isoforms of the Na+/K+-ATPase α subunit were found in SMCs but based on ouabain-sensitivity and co-precipitation experiments we suggest that α2 Na+/K+-ATPase subunit is involved in regulation of the intercellular communication.We have here shown that gap junctions between SMCs are regulated through an interaction between the Na+/K+-ATPase and the Na+/Ca2+-exchanger leading to an increase in [Ca2+]i in discrete areas near the plasma membrane. We have also suggested that this Na+/K+-pump-containing microdomain is functionally linked to KATP channels via the local ion homeostasis.

AB - The Na+/K+-ATPase is known to interact with many membrane and cytosolic proteins by organizing various signaling complexes. These interactions were suggested to be important in regulation of various cellular responses. Pumping activity of the Na+/K+-ATPase is suggested to be essential for some of these interactions, while other responses may be independent of pumping activity. The Na+/K+-pump differs from other P-type ATPases by its sensitivity to cardiotonic steroids such as ouabain. However, rodent tissues express both ouabain-insensitive (α1) and ouabain-sensitive (α2 and α3) isoforms of Na+/K+-ATPases. Based on our previous findings we hypothesized here that the ouabain-sensitive isoform of the Na+/K+-ATPase can regulate vascular tone by interaction with Na+/Ca2+-exchanger, gap junctions and KATP channels.[Ca2+]i in individual smooth muscle cells (SMCs) was imaged simultaneously with isometric force in rat mesenteric small arteries. Paired cultured rat smooth muscle cells (A7r5) were used as a model for electrical coupling of SMC by measuring membrane capacitance (Cm). PCR, Western blotting and immunohistochemistry were used to identify the membrane transporters. SMCs were uncoupled (evaluated by inhibition of vasomotion and desynchronization of [Ca2+]i transients in the vascular wall, or by reduction of Cm measured in paired A7r5 cells) when the Na+/K+-ATPase was inhibited either by a low concentration of ouabain (1-10 µM) or by ATP depletion. Inhibition of the Na+/Ca2+-exchange activity by SEA0400 or by lowering the extracellular Na+ concentration also uncoupled the cells. Reduction of Na+/K+-ATPase activity by removal of extracellular K+ uncoupled cells, but only after inhibition of KATP channels. This interaction was bidirectional. Depletion of [Na+]i and clamping [Ca2+]i at low levels prevented the uncoupling. Low ouabain concentration evoked spatially restricted [Ca2+]i transients along the cell periphery.All three isoforms of the Na+/K+-ATPase α subunit were found in SMCs but based on ouabain-sensitivity and co-precipitation experiments we suggest that α2 Na+/K+-ATPase subunit is involved in regulation of the intercellular communication.We have here shown that gap junctions between SMCs are regulated through an interaction between the Na+/K+-ATPase and the Na+/Ca2+-exchanger leading to an increase in [Ca2+]i in discrete areas near the plasma membrane. We have also suggested that this Na+/K+-pump-containing microdomain is functionally linked to KATP channels via the local ion homeostasis.

M3 - Poster

Y2 - 5 August 2008 through 10 August 2008

ER -