Garg M L, Wierzbicki A A, Thomson A B, Clandinin M T
Department of Foods and Nutrition, University of Alberta, Edmonton, Canada.
Lipids. 1989 Apr;24(4):334-9. doi: 10.1007/BF02535173.
Male weanling rats were fed semi-synthetic diets high in saturated fat (beef tallow) vs high in linoleic acid (safflower oil) with or without high levels of alpha-linolenic acid (linseed oil) for a period of 28 days. The effect of feeding these diets on cholesterol content and fatty acid composition of serum and liver lipids was examined. Feeding linseed oil with beef tallow or safflower oil had no significant effect on serum levels of cholesterol. Serum cholesterol concentration was higher in animals fed the safflower oil diet than in animals fed the beef tallow diet without linseed oil. Feeding linseed oil lowered the cholesterol content in liver tissue for all dietary treatments tested. Consumption of linseed oil reduced the arachidonic acid content with concomitant increase in linoleic acid in serum and liver lipid fractions only when fed in combination with beef tallow, but not when fed with safflower oil. Similarly, omega 3 fatty acids (18:3 omega 3, 20:5 omega 3, 22:5 omega 3, 22:6 omega 3) replaced omega 6 fatty acids (20:4 omega 6, 22:4 omega 6, 22:5 omega 6) in serum and liver lipid fractions to a greater extent when linseed oil was fed with beef tallow than with safflower oil. The results suggest that the dietary ratio of linoleic acid to saturated fatty acids or of 18:3 omega 3 to 18:2 omega 6 may be important to determine the cholesterol and arachidonic acid lowering effect of dietary alpha-linolenic acid.
雄性断奶大鼠被喂食富含饱和脂肪（牛油）或富含亚油酸（红花油）的半合成饲料，饲料中添加或不添加高水平的α-亚麻酸（亚麻籽油），持续28天。研究了这些饮食对血清和肝脏脂质中胆固醇含量及脂肪酸组成的影响。将亚麻籽油与牛油或红花油一起喂食，对血清胆固醇水平没有显著影响。喂食红花油饲料的动物血清胆固醇浓度高于未添加亚麻籽油的牛油饲料组动物。对于所有测试的饮食处理，喂食亚麻籽油均可降低肝脏组织中的胆固醇含量。仅在与牛油一起喂食时，食用亚麻籽油才会降低血清和肝脏脂质组分中的花生四烯酸含量，同时伴随着亚油酸含量的增加，而与红花油一起喂食时则不会。同样，当亚麻籽油与牛油一起喂食时，血清和肝脏脂质组分中的ω-3脂肪酸（18:3 ω-3、20:5 ω-3、22:5 ω-3、22:6 ω-3）比与红花油一起喂食时能更大程度地替代ω-6脂肪酸（20:4 ω-6、22:4 ω-6、22:5 ω-6）。结果表明，亚油酸与饱和脂肪酸的饮食比例或18:3 ω-3与18:2 ω-6的比例可能对确定饮食中α-亚麻酸降低胆固醇和花生四烯酸的效果很重要。
