Comparison of atherosclerotic lesions and HDL-lipid levels in male, female, and testosterone-treated female mice from strains C57BL/6, BALB/c, and C3H.
In order to determine whether male and female mice differed in HDL-lipid levels or in atherosclerotic response to a high fat diet, we examined 3 inbred strains which differed in susceptibility to atherosclerosis; C57BL/6, BALB/c, and C3H. Mice were fed normal chow or an atherogenic diet containing 1.25% cholesterol, 15% fat, and 0.5% cholic acid. Lesion number and size were determined after 14 weeks on the diet; plasma HDL-lipid levels were determined at 0 and 4 weeks on the diet. For C3H, the most atherosclerosis-resistant strain, HDL-lipid levels were very high and not affected by sex or diet. For BALB/c, HDL-lipid levels were intermediate between the other two strains. Male levels were significantly higher than the females, and the atherogenic diet caused a drop in HDL-lipid levels of 14-27% depending on sex. For C57BL/6, the most atherosclerosis-susceptible strain, HDL-lipid levels were low compared to the other two strains. Males and females on normal chow did not differ in HDL-lipid, but females showed a 50% decrease in HDL when fed the atherogenic diet. For both BALB/c and C57BL/6, testosterone-treated females resembled the males. The HDL-lipid levels in mice on atherogenic diet differed over a 3-fold range among the nine groups. When HDL-lipid levels were compared to the number of atherosclerotic lesions or the total lesion area, a high degree of correlation was observed (r = -0.95 for lesion number and -0.93 for total lesion area). This suggests that HDL-lipid levels are important in determining atherosclerosis susceptibility in mice.
D000818:Animals; D001161:Arteriosclerosis / Q000097:blood / Q000473:pathology / Q000517:prevention & control*; D005260:Female; D008075:Lipoproteins, HDL / Q000097:blood*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D012737:Sex Factors; D013045:Species Specificity; D013739:Testosterone / Q000627:therapeutic use*
D008075:Lipoproteins, HDL; D013739:Testosterone