| Abstract: | 本實驗設計探討飲食中油脂種類與維生素E量多寡對於血液中前列腺素和各種脂肪濃度的影響,因為血液中前列腺素和脂肪濃度可以作為發生動脈血管硬化的一個危險指標。利用四十隻剛離乳雄性Sprague-Dawley老鼠分別餵食含有不同濃度Linoleate和維生素E飲食,看它對血液中脂肪酸成分、脂肪過氧化情形、維生素E、Thromboxane B/sub 2/、6-keto-prostaglandinF/sub 1.alpha./、總膽固醇、HDL-膽固醇、LDL-膽固醇和三酸甘油脂濃度的影響。老鼠分別餵食含3.5或18.4%能量由Linoleate提供的飲食,其中每種又各含有0,100,5,000或是15,000ppm維生素E,所以共有八種不同飼料配方,餵食時間為八週,餵食15,000ppm維生素E的老鼠,血液中有最高維生素E濃度,而吃不含維生素E飼料的老鼠,其血液中維生素E濃度最低。血液中硬脂酸和油酸濃度在3.5en% Linoleate這組比18.4en% Linoleate這組要來得高,而Linoleate和Arachidonate在18.4en% Linoleate這組要比3.5en% Linoleate這組高出許多。不同飲食對老鼠的食物攝取量,體重增加情形及血液中三酸甘油脂的濃度並無影響。血液中TXB/sub 2/和脂肪過氧化情形在維生素E缺乏這組比其他組要高,血液中HDL-膽固醇濃度在維生素E缺乏這組比其他組別的老鼠來得低,然而維生素E缺乏的老鼠其血液中LDL-膽固醇濃度與其他組別的老鼠比較卻顯然來得高。增加飲食中Linoleate可能可以藉由它對血液中HDL-膽固醇濃度的影響來達到預防心臟血管疾病發生的目的。維生素E缺乏引起血液中TXB/sub 2/和LDL-膽固醇濃度的上升及HDL-膽固醇濃度的下降,所以維生素E缺乏可能對心臟血管疾病的發生有不利的影響,與維生素E足夠的組別比較,額外補充維生素E對於預防心血管疾病的發生似乎沒有特別的效用。
The experiment was designed to study the effects of dietary fat and vitamin E on serum prostaglandin and lipid status, two indicators of risk for atherosclerosis. The influences of increasing dietary linoleate and d,1-.alpha.-tocopheryl acetate (vitamin E) on serum fatty acid composition, lipid peroxidation, vitamin E, thromboxane B/sub 2/ (TXB/sub 2/), 6-keto-prostaglandin F/sub 1.alpha./(6-keto-PGF/sub 1.alpha./), total cholesterol, HDL-cholesterol, LDL-cholesterol and triglyceride concentrations were studied in 40 weanling male Sprague-Dawley rats. Rats were fed semipurified diets containing 3.5 or 18.4% of energy from linoleate (en%), and graded levels (0, 100, 5,000 or 15,000ppm) of vitamin E for 8 weeks. Vitamin E status was confirmed by serum vitamin E levels. Rats fed no vitamin E had the lowest serum vitamin E concentrations while rats fed 15,000ppm vitamin E had the greatest serum vitamin E (p<0.05). Lipid status was verified by serum fatty acid composition. Serum C18:0 (stearic acid) and C18:1 n-9 (oleic acid) of rats were significantly greater in the 3.5en% linoleate group than in the 18.4en% linoleate group, and serum C18:2 n-6 (linoleic acid) and C20:4 n-6 (arachidonic acid) of rats were significantly greater in the 18.4en% linoleate group than in the 3.5en% linoleate group (p<0.05). The treatments had no effect no food intake, body weight gain and serum triglyceride concentrations. Serum TXB/sub 2/ and lipid peroxidation (TBARS) were significantly greater in the vitamin E-deficient rats than in vitamin E-adequate and vitamin E-supplemented rats (p<0.05). Serum HDL-cholesterol level was significantly greater in the vitamin E-treated rats compared with rats fed no vitamin E (p<0.05). However, serum LDL-cholesterol level was significantly greater in the rats fed no vitamin E compared with rats treated with vitamin E. |
