Fig. 5

Effects of the APOE allele vs APOE contents on Ca²⁺-based excitability. aAPOE mRNA expression relative to Gapdh and 18S mRNA contents in APOE3 and APOE4 immortalized astrocytes, quantified by real time qPCR (N = 3). b Representative ApoE western blot of APOE3 cells transfected with scramble or APOE siRNA. c Representative traces and quantification of the magnitude of ATP-induced Ca²⁺ responses in APOE3 astrocytes transfected with lipofectamine (lipo), plus scramble (sc) or APOE siRNA, and APOE4 astrocytes treated only with lipofectamine (N = 4). d Representative images of immunocytochemistry of APOE3 and APOE4 cells transfected with plasmids expressing GFP, GFP-APOE4, and GFP-APOE3, as indicated. Scale bar represents 15 μm. e Representative traces and quantification of the magnitude of 100 μM ATP-elicited Ca²⁺ responses in APOE3 and APOE4 cells transfected with different plasmids as indicated. Ca²⁺ peaks after ATP stimulation are relative to the responses of APOE3 cells transfected with GFP. Only GFP fluorescent cells were analyzed (at least 30 cells from 4 independent experiments). f Quantification of the magnitude of Ca²⁺ responses elicited by 100 μM ATP in APOE3 astrocytes transfected with GFP or GFP-APOE4 plasmids, as indicated. Ca²⁺ peaks after ATP stimulation are relative to the responses of APOE3 cells transfected with GFP. Only GFP fluorescent cells were analyzed (at least 30 cells from 4 independent experiments). g Representative images of Lamp1 (red) and ApoE (green) immunocytochemistry in APOE3 cells. Merged images and amplifications of the area in the white frame, are displayed. Scale bar represents 15 μm. h Representative images of Lamp1 immunocytochemistry (red) and GFP-ApoE fluorescence (green) in APOE4 cells. Merged images and the amplification of a cell of each image, indicated with a white frame, are displayed. Scale bar represents 15 μm. Unpaired parametric T-test was used in a, and one-way ANOVA in c and e. p < 0.05 (*), p < 0.01 (**), p < 0.001 (***), p < 0.0001 (****)