Fig. 2. Kv4 channels and CaMKII are differentially located in membrane rafts. A) Sucrose density gradient fractions of detergent-free extracted membrane rafts from rat ventricular myocytes. The presence of Caveolin-3 only in the low density fractions (5-35%) and Na⁺/K⁺ ATPase only at the bottom of the gradient demonstrate effective separation of raft from non-raft plasma membrane. B) Representative sucrose density gradients obtained from ventricular samples in control conditions or after pre-incubation with 2% M-β-CD or 5 μM colchicine. C) Quantification of the percentage of raft-located proteins in control conditions and after each treatment. Each western blot shown is representative of 8 different gradients.