Figure 3.

Lipid analysis. A, B, Lipids were extracted from brains of young (6 months) (A) and aged (20–24 months) (B) ASA(+/−), tg/ASA(+/−), ASA(−/−), and tg/ASA(−/−) mice. C, In addition, myelin was purified by sucrose gradient centrifugation from brains of 20- to 24-month-old mice. The amount of lipids corresponding to 0.125 mg of brain wet weight was loaded per lane. Sulfatide, GalC, and phosphatidyl ethanolamine levels were determined by densitometry, and sulfatide and GalC levels were normalized to phosphatidyl ethanolamine. D–F, Sulfatide levels (mean ± SD; n = 3) and GalC levels after normalization to phosphatidyl ethanolamine; lipid levels in ASA(+/−) samples were set to 100%. The data shown are from mice of the transgenic line tg2639; similar results, however, were obtained with samples from the second line, tg2645 (data not shown). G, H, Lipid analysis of the plexus brachialis from 20- to 24-month-old mice of the indicated genotypes. Sulfatide levels were determined as described above for brain lipids [mean ± SD; n = 3, except for ASA(+/−) (n = 2)]. I, J, Lipid analysis of sciatic nerves from 18-month-old ASA(−/−) and tg/ASA(−/−) mice (mean ± SD; n = 3). Asterisks indicate statistically significant differences (p < 0.05, ANOVA with post hoc Bonferroni test). Sulf, Sulfatide; PE, phosphatidyl ethanolamine.