Rajni Sudhir1, Nadim Jaafar2, Qingyou Du1, Andriy Sukhodub1, Sofija Jovanović1, Magdalini Kreouzi2, Aleksandar Jovanović2,3. 1. Department of Molecular and Clinical Medicine, University of Dundee, Dundee, Scotland, UK. 2. Department of Basic and Clinical Sciences, University of Nicosia Medical School, Nicosia, Cyprus. 3. Center for Neuroscience and Integrative Brain Research (CENIBRE), University of Nicosia Medical School, Nicosia, Cyprus.
Abstract
OBJECTIVES: SUR2A is an ABC protein serving as a regulatory subunit of ATP-sensitive (KATP) channels. An increase in SUR2A levels is cardioprotective and it is a potential therapeutic strategy against ischaemic heart disease, heart failure and other diseases. However, whether overexpression of this protein has any adverse effects is yet to be fully understood. Here, we examined the heart rate and the heart rate diurnal variation in mice overexpressing SUR2A (SUR2A+) and their littermate controls (WT) using ECG telemetry that was continuously recorded for 14 days (days 8-23 post-radiotransmitter implantation). METHODS: Using SigmaPlot 14.0 and Microsoft Excel, Area Under the Curve (AUC) for each parameter was calculated and plotted in a graph. RESULTS: Both WT and SUR2A+ mice were more physically active during nights and there were no significant differences between two phenotypes. Physical activity was associated with increased heart rate in both phenotypes, but there were no differences in heart rate between phenotypes irrespective of physical activity or time of the day. A diurnal heart rate variation was preserved in the SUR2A+ mice. As area under the curve (AUC) analysis has the potential to reveal differences that are invisible with other statistical methods, we compared AUC of heart rate in SUR2A+ and WT mice. This analysis did not yield anything different from traditional analysis. CONCLUSIONS: We conclude that increased SUR2A levels are not associated with changes in physical activity, heart rate and/or circadian rhythm influence on the heart rate. This lack of adverse effects supports a notion that manipulation with SUR2A levels is a promising cardioprotective strategy.
OBJECTIVES: SUR2A is an ABC protein serving as a regulatory subunit of ATP-sensitive (KATP) channels. An increase in SUR2A levels is cardioprotective and it is a potential therapeutic strategy against ischaemic heart disease, heart failure and other diseases. However, whether overexpression of this protein has any adverse effects is yet to be fully understood. Here, we examined the heart rate and the heart rate diurnal variation in mice overexpressing SUR2A (SUR2A+) and their littermate controls (WT) using ECG telemetry that was continuously recorded for 14 days (days 8-23 post-radiotransmitter implantation). METHODS: Using SigmaPlot 14.0 and Microsoft Excel, Area Under the Curve (AUC) for each parameter was calculated and plotted in a graph. RESULTS: Both WT and SUR2A+ mice were more physically active during nights and there were no significant differences between two phenotypes. Physical activity was associated with increased heart rate in both phenotypes, but there were no differences in heart rate between phenotypes irrespective of physical activity or time of the day. A diurnal heart rate variation was preserved in the SUR2A+ mice. As area under the curve (AUC) analysis has the potential to reveal differences that are invisible with other statistical methods, we compared AUC of heart rate in SUR2A+ and WT mice. This analysis did not yield anything different from traditional analysis. CONCLUSIONS: We conclude that increased SUR2A levels are not associated with changes in physical activity, heart rate and/or circadian rhythm influence on the heart rate. This lack of adverse effects supports a notion that manipulation with SUR2A levels is a promising cardioprotective strategy.
Authors: Sofija Jovanović; Qingyou Du; Russell M Crawford; Grant R Budas; Igor Stagljar; Aleksandar Jovanović Journal: EMBO Rep Date: 2005-09 Impact factor: 8.807
Authors: Russell M Crawford; Harri J Ranki; Catherine H Botting; Grant R Budas; Aleksandar Jovanovic Journal: FASEB J Date: 2001-11-29 Impact factor: 5.191