Increase of ATP-sensitive potassium (K<sub>ATP</sub>) channels in the heart of type-1 diabetic rats

<p>Abstract</p> <p>Background</p> <p>An impairment of cardiovascular function in streptozotocin (STZ)-diabetic rats has been mentioned within 5 days-to-3 months of induction. ATP-sensitive potassium (K<sub>ATP</sub>) channels are expressed on cardiac sarcole...

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Main Authors: Chen Zhih-Cherng, Cheng Yung-Ze, Chen Li-Jen, Cheng Kai-Chun, Li Yin-, Cheng Juei-
Format: Article
Language:English
Published: BMC 2012-01-01
Series:Cardiovascular Diabetology
Subjects:
Online Access:http://www.cardiab.com/content/11/1/8
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author Chen Zhih-Cherng
Cheng Yung-Ze
Chen Li-Jen
Cheng Kai-Chun
Li Yin-
Cheng Juei-
author_facet Chen Zhih-Cherng
Cheng Yung-Ze
Chen Li-Jen
Cheng Kai-Chun
Li Yin-
Cheng Juei-
author_sort Chen Zhih-Cherng
collection DOAJ
description <p>Abstract</p> <p>Background</p> <p>An impairment of cardiovascular function in streptozotocin (STZ)-diabetic rats has been mentioned within 5 days-to-3 months of induction. ATP-sensitive potassium (K<sub>ATP</sub>) channels are expressed on cardiac sarcolemmal membranes. It is highly responsive to metabolic fluctuations and can have effects on cardiac contractility. The present study attempted to clarify the changes of cardiac K<sub>ATP </sub>channels in diabetic disorders.</p> <p>Methods</p> <p>Streptozotocin-induced diabetic rats and neonatal rat cardiomyocytes treated with a high concentration of glucose (a D-glucose concentration of 30 mM was used and cells were cultured for 24 hr) were used to examine the effect of hyperglycemia on cardiac function and the expression of K<sub>ATP </sub>channels. K<sub>ATP </sub>channels expression was found to be linked to cardiac tonic dysfunction, and we evaluated the expression levels of K<sub>ATP </sub>channels by Western blot and Northern blot analysis.</p> <p>Results</p> <p>The result shows diazoxide produced a marked reduction of heart rate in control group. Furthermore, the methods of Northern blotting and Western blotting were employed to identify the gene expression of K<sub>ATP </sub>channel. Two subunits of cardiac K<sub>ATP </sub>channel (SUR2A and kir 6.2) were purchased as indicators and showed significantly decreased in both diabetic rats and high glucose treated rat cardiac myocytes. Correction of hyperglycemia by insulin or phlorizin restored the gene expression of cardiac K<sub>ATP </sub>in these diabetic rats.</p> <p>Conclusions</p> <p>Both mRNA and protein expression of cardiac K<sub>ATP </sub>channels are decreased in diabetic rats induced by STZ for 8 weeks. This phenomenon leads to result in desensitization of some K<sub>ATP </sub>channel drugs.</p>
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spelling doaj.art-0e3f32a7cf064eba81b298923a47fcbf2022-12-22T01:08:27ZengBMCCardiovascular Diabetology1475-28402012-01-01111810.1186/1475-2840-11-8Increase of ATP-sensitive potassium (K<sub>ATP</sub>) channels in the heart of type-1 diabetic ratsChen Zhih-CherngCheng Yung-ZeChen Li-JenCheng Kai-ChunLi Yin-Cheng Juei-<p>Abstract</p> <p>Background</p> <p>An impairment of cardiovascular function in streptozotocin (STZ)-diabetic rats has been mentioned within 5 days-to-3 months of induction. ATP-sensitive potassium (K<sub>ATP</sub>) channels are expressed on cardiac sarcolemmal membranes. It is highly responsive to metabolic fluctuations and can have effects on cardiac contractility. The present study attempted to clarify the changes of cardiac K<sub>ATP </sub>channels in diabetic disorders.</p> <p>Methods</p> <p>Streptozotocin-induced diabetic rats and neonatal rat cardiomyocytes treated with a high concentration of glucose (a D-glucose concentration of 30 mM was used and cells were cultured for 24 hr) were used to examine the effect of hyperglycemia on cardiac function and the expression of K<sub>ATP </sub>channels. K<sub>ATP </sub>channels expression was found to be linked to cardiac tonic dysfunction, and we evaluated the expression levels of K<sub>ATP </sub>channels by Western blot and Northern blot analysis.</p> <p>Results</p> <p>The result shows diazoxide produced a marked reduction of heart rate in control group. Furthermore, the methods of Northern blotting and Western blotting were employed to identify the gene expression of K<sub>ATP </sub>channel. Two subunits of cardiac K<sub>ATP </sub>channel (SUR2A and kir 6.2) were purchased as indicators and showed significantly decreased in both diabetic rats and high glucose treated rat cardiac myocytes. Correction of hyperglycemia by insulin or phlorizin restored the gene expression of cardiac K<sub>ATP </sub>in these diabetic rats.</p> <p>Conclusions</p> <p>Both mRNA and protein expression of cardiac K<sub>ATP </sub>channels are decreased in diabetic rats induced by STZ for 8 weeks. This phenomenon leads to result in desensitization of some K<sub>ATP </sub>channel drugs.</p>http://www.cardiab.com/content/11/1/8Cardiac ATP-sensitive potassium channelGene expressionInsulinPhlorizinDiabetic rats
spellingShingle Chen Zhih-Cherng
Cheng Yung-Ze
Chen Li-Jen
Cheng Kai-Chun
Li Yin-
Cheng Juei-
Increase of ATP-sensitive potassium (K<sub>ATP</sub>) channels in the heart of type-1 diabetic rats
Cardiovascular Diabetology
Cardiac ATP-sensitive potassium channel
Gene expression
Insulin
Phlorizin
Diabetic rats
title Increase of ATP-sensitive potassium (K<sub>ATP</sub>) channels in the heart of type-1 diabetic rats
title_full Increase of ATP-sensitive potassium (K<sub>ATP</sub>) channels in the heart of type-1 diabetic rats
title_fullStr Increase of ATP-sensitive potassium (K<sub>ATP</sub>) channels in the heart of type-1 diabetic rats
title_full_unstemmed Increase of ATP-sensitive potassium (K<sub>ATP</sub>) channels in the heart of type-1 diabetic rats
title_short Increase of ATP-sensitive potassium (K<sub>ATP</sub>) channels in the heart of type-1 diabetic rats
title_sort increase of atp sensitive potassium k sub atp sub channels in the heart of type 1 diabetic rats
topic Cardiac ATP-sensitive potassium channel
Gene expression
Insulin
Phlorizin
Diabetic rats
url http://www.cardiab.com/content/11/1/8
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