Figure 6

Sterol analyses in brain tissues from wild-type, knockout and knockout- transgenic pups. A slightly elevated cholesterol level was found in Dhcr7^-/-Tg+ brains, compared to Dhcr7^-/-Tg- brains (0.58 ± 0.03 mg/g brain tissue in Dhcr7^-/-Tg+ vs. 0.47 ± 0.06 mg/g brain tissue in Dhcr7^-/-Tg-, p < 0.05, see Text for discussion) (Panel A). However, there were no significant alterations of 7/8DHC levels (3.42 ± 0.53 mg/g tissue in Dhcr7^-/-Tg+ vs. 3.01 ± 0.38 mg/g tissue in Dhcr7^-/-Tg-, p > 0.05) (Panel B), or of the ratios of different precursors in Dhcr7^-/-Tg+ (89 ± 1 %), compared to Dhcr7^-/-Tg- brains (91 ± 2 %, p > 0.05) (Panel C). No significant difference (p > 0.05) was found in brain total sterol levels among three groups (mg/g tissue: 4.63 ± 0.46 in WT, 5.05 ± 0.68 in Dhcr7^-/-Tg- and 5.33 ± 0.66 in Dhcr7^-/-Tg+, data not shown). Results are expressed as mean ± SD.