SERCA2 and SERCA3 Shift to a More Nuclear and Perinuclear Distribution in Conditions of Diabetes and Hyperglycemia. Immunofluorescence shows the distribution of proteins in cells from control and diabetic rats from both the DR-BB (A, B, G, and H) and STZ diabetic model (C, D, I, and J), and in A7r5 cells cultured with medium (E and K) or high glucose concentrations (F and L). Examples show a more localized perinuclear and nuclear distribution of SERCA2 in both animal models when diabetes was developed. In addition there was a decrease in the total fluorescence for SERCA3 in both animal models. Hyperglycemia also induced a redistribution of SERCA2 and SERCA3 to the nucleus.