Figure 4.

Western blot analysis of apo E, APP, and LRP in hippocampal and cortical tissue lysates in APP^V717F+/– mice. (a) Apo E levels in mouse apo E^+/+ mice were similar to that seen in APP^V717F+/–, apo E4^+/– line 22 mice, and there were no significant differences in human APP or LRP levels between the groups. For hippocampal samples, 30 μg of detergent-soluble protein from individual 39-week-old mice was loaded per lane. Lanes 1 and 4, apo E4^+/– line 22. Lanes 2 and 5, apo E^–/–. Lanes 3 and 6, mouse apo E^+/+. Human apo E is seen as a doublet (∼35 and 37 kDa) due to a sialylated form; a single band is observed for mouse apoE (∼34 kDa). Human APP is ∼120 kDa, and the transmembrane subunit of LRP is ∼85 kDa. (b) Apo E levels are similar in the different human apo E transgenic lines. Detergent-soluble protein (50 μg) from the cortex of individual mice was loaded to each lane. Lanes 1 and 2, apo E3^+/– line 37. Lanes 3 and 4, apo E4^+/– line 11. Lanes 5 and 6, apo E4^+/– line 22. There was no significant difference in the level of human APP or of LRP between any of the groups of mice either qualitatively as shown here or quantitatively as assessed by densitometric analysis (data not shown). LRP, low-density lipoprotein receptor–related protein.