Document Type : Original Article
Authors
1 Ph.D., Associate Professor, Colorectal research center, Shiraz University of medical sciences, Shiraz, Iran
2 M.D., Assistant Professor, Neurology Department, Faculty of Medicine, Shiraz University of medical sciences, Shiraz, Iran
Abstract
Introduction: Cardiac Na+ channels are responsible for the excitation of the cardiac cells. Hyperglycemia is the chief symptom of diabetes and several other complications. Although many studies have been conducted on diabetic cardiomyopathy, the role of high glucose on sodium current has not been completely clarified. In the present study, the authors investigated the role of high glucose concentration on human cardiac sodium channels current in transfected HEK293 cells.
Methods: The authors evaluatedglucose effects on sodium current using the whole-cell patch-clamp technique.
Results: The data indicated that Na+ current was significantly modified with an overnight exposure to high glucose. For steady-state activation, high glucose-induced insignificant hyperpolarizing shifted the V1/2. Steady-state inactivation shifted to more negative potentials with glucose exposure (p < 0.001).
Conclusions: Data suggested that the glucose effect on two forms of sodium channel gates (activation and inactivation) raises the possibility of metabolic modulations of sodium channel activity. A hyperpolarized shift of activation and inactivation is supposed to enhance cardiac cell excitability.
Keywords
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