Effects of interleukin-6 on the bio-electric activity of rat atrial tissue under normal conditions and during gradual stretching

• Mechano-gated channels play critical role in the IL-6 induced myocardial dysfunction.
• High IL-6 levels are exclusively connected with the atrial fibrillation.
• IL-6 enhances the occurrence of atrial fibrillation induced by stretch.
• IL-6 plays the role of initiator of the STAT phosphorylation as a basic mechanism involved in the MGCs regulation.

Using the micro-electrode technique we studied the effects of interleukin-6 on bio-electric activity of rat atrial tissue under normal conditions and after gradual stretching. It was shown that IL-6 caused increasing of the duration of the action potential at the levels of 25, 50, and 90% re-polarization. The hump-like depolarization at APD90 appeared 7–10 min after initial stretching and transformed into single extra-potentials after tension removing. Perfusion with IL-6 for more than 20 min led to the appearance of atrial fibrillation even with the application of slight tension. Close observation of the IL-6 induced mechanisms and stretch induced APD alteration, confirmed the existence of a tight link between examined cytokine and stretch induced mechanisms.