IL-1 provokes electrical abnormalities in rat atrial myocardium

Using a micro-electrode technique we studied the effects of interleukin 1 alpha and interleukin 1 beta on bio-electric activity of rat atrial myocardium under normal conditions and after gradual stretching. Perfusion with interleukin la increased the duration of the action potential at the level of 90% re-polarization. Stretch induced tachy-arrhythmia in the presence of interleukin la is mainly regulated via stretch increased nitric oxide production, while the ionotropic effect of the interleukin-1 alpha during stretching is not pronounced. The perfusion with interleukin 1 beta did not change the values of the duration of the action potentials at the levels of 25,50 and 90% repolarization. The interleukin 1 beta caused an appearance of extra-systolic patterns which turned into normal rhythm, alternating with periods of normal activity. The total intracellular nitric oxide level induced by both interleukin 1 beta and stretching is balanced by interleuldn-1 beta induced cation influx. (C) 2015 Elsevier B.V. All rights reserved.