Cecil H C, Bitman J, Svoboda J A, Thompson M J
Poult Sci. 1981 Apr;60(4):795-804. doi: 10.3382/ps.0600795.
Six branched and straight chain secondary or tertiary amines with chain lengths of 12 to 18 carbons and two azasteroids, 25-aza-5 alpha-cholestane and 25-azacoprostane, were fed to mature White Leghorn hens, and their effectiveness was compared with 20,25-diazacholesterol dihydrochloride (SC-12937), an azasteroid known to lower egg cholesterol. Feed consumption, body weight, egg production, egg and plasma cholesterol and desmosterol, and plasma total lipid were measured. The 6 amines were fed at 200 ppm, and only the C12 branched chain amine N,N,3,711-pentamethyldodecanamine reduced plasma and egg cholesterol with a concomitant increase in desmosterol. After 4 weeks, plasma desmosterol was 0, 13, 60, and 75% of total sterol for control, 200 ppm C12 branched chain amine, 5 ppm diazacholesterol, and 5 ppm azacholestane, respectively. Egg production was severely reduced to 6 and 0% by feeding 5 ppm azacholestane for 2 and 4 weeks, respectively, and to 69 and 36% by feeding 5 ppm diazacholesterol. After 4 weeks egg cholesterol was 79 and 36% of the total sterol for the 200 ppm C12 branched chain amine and 5 ppm diazacholesterol, respectively. Concomitant increases in desmosterol accompanied all reductions in cholesterol. The depletion and repletion rates of egg cholesterol were measured in a subsequent experiment. After 2-1/2 weeks of feeding the test substances, egg cholesterol was reduced with concomitant increases in desmosterol. Egg cholesterol was 100, 71, and 50% of the total egg sterol for control, 200 ppm, and 400 ppm C12 branched chain amine, respectively: 58, 13, and 3% for .1, .5, and 1.0 ppm azacholestane; 28, 29, and 18% for 1, 2.5, and 5 ppm azacholesterol; and 23% for 1 ppm azacoprostane. The experimental diets were then withdrawn, and egg cholesterol repletion was studied biweekly. Egg cholesterol was repleted to 100% of the total sterol after withdrawal times of 2 weeks for C12 branched chain amine, 8 weeks for azacoprpostane, 14 to 16 weeks for diazacholesterol, 10 to 16 weeks for the lower levels of azacholestane, and longer than 16 weeks for 1 ppm azacholestane. The increase in desmosterol accompaning the demonstrated reduction in egg cholesterol, particularly with azasteroids, causes one to question the usefulness of this approach to lower cholesterol.
将六种碳链长度为12至18个碳的支链和直链仲胺或叔胺以及两种氮杂甾体化合物,即25 - 氮杂 - 5α - 胆甾烷和25 - 氮杂 - 前列烷,投喂给成熟的白来航母鸡,并将它们的效果与20,25 - 二氮杂胆固醇二盐酸盐(SC - 12937)进行比较,SC - 12937是一种已知可降低鸡蛋胆固醇的氮杂甾体化合物。测量了采食量、体重、产蛋量、鸡蛋和血浆中的胆固醇及去氢胆固醇,以及血浆总脂质。六种胺的投喂浓度为200 ppm,只有C12支链胺N,N,3,7,11 - 五甲基十二烷胺降低了血浆和鸡蛋中的胆固醇,同时去氢胆固醇增加。4周后,对照组、200 ppm C12支链胺组、5 ppm二氮杂胆固醇组和5 ppm氮杂胆甾烷组血浆中去氢胆固醇分别占总甾醇的0%、13%、60%和75%。分别投喂5 ppm氮杂胆甾烷2周和4周后,产蛋量严重降至6%和0%,投喂5 ppm二氮杂胆固醇后产蛋量降至69%和36%。4周后,200 ppm C12支链胺组和5 ppm二氮杂胆固醇组鸡蛋胆固醇分别占总甾醇的79%和36%。胆固醇的所有降低都伴随着去氢胆固醇的增加。在随后的实验中测量了鸡蛋胆固醇的消耗和补充率。投喂测试物质2.5周后,鸡蛋胆固醇降低,同时去氢胆固醇增加。对照组、200 ppm和400 ppm C12支链胺组鸡蛋胆固醇分别占总蛋甾醇的100%、71%和50%;0.1、0.5和1.0 ppm氮杂胆甾烷组分别为58%、13%和3%;1、2.5和5 ppm二氮杂胆固醇组分别为28%、29%和18%;1 ppm氮杂前列烷组为23%。然后撤去实验日粮,每两周研究一次鸡蛋胆固醇的补充情况。撤去日粮后,C12支链胺2周后鸡蛋胆固醇补充至总甾醇的100%,氮杂前列烷8周,二氮杂胆固醇14至16周,较低剂量氮杂胆甾烷10至16周,1 ppm氮杂胆甾烷超过16周。伴随鸡蛋胆固醇明显降低而出现的去氢胆固醇增加,特别是使用氮杂甾体化合物时,让人质疑这种降低胆固醇方法的有效性。