EN
In this study, a fixation protocol using a 10% neutral buffered formalin (FA) solution and another protocol using a methanol (MeOH) solution were compared for detection of ion channels, Kᵥ 1.5, Kᵥ 4.2, Caᵥ 1.2, Kᵢᵣ6.2, Naᵥ 1.5 and Naᵥ 1.1 in rat myocytes by immunolabelling. Kᵥ 1.5 and Kᵥ 4.2 at intercalated discs and Caᵥ 1.2 at transverse tubules were not detected by FA but were detected by MeOH. Kᵢᵣ6.2 at transverse tubules and Naᵥ 1.5 at sarcolemma were detected by FA but not by MeOH. It is suggested that both FA and MeOH fixation protocols should be used for the detection of cardiac ion channels by immunolabelling. (Folia Morphol 2015; 74, 2: 258–261)