Dietary cholesterol does not affect the synthesis of apolipoproteins B and E by rat hepatocytes.
Dietary cholesterol does not affect the synthesis of apolipoproteins B and E by rat hepatocytes.
复制标题
膳食胆固醇不影响大鼠肝细胞合成载脂蛋白B和E。
DOI：
10.1042/bj2270029
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发表时间：
1985
期刊：
影响因子：
--
通讯作者：
Malone-McNeal,M
中科院分区：
文献类型：
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作者：
Davis,RA;Malone-McNeal,M
为了检验膳食胆固醇影响载脂蛋白 B 和 E 合成这一未经证实的假设，我们给大鼠喂食富含胆固醇的饮食，该饮食已被证明可以显着改变这些载脂蛋白的血清浓度。喂食富含胆固醇饮食 4 周的大鼠血清中低 Mr 载脂蛋白 B 的浓度增加（+2.7 倍），载脂蛋白 E 的浓度降低（-40%）。将获自类似处理的大鼠的肝细胞置于单层培养物中，并测定载脂蛋白的从头合成速率。尽管在整个实验期间，来自胆固醇喂养的大鼠的细胞仍然充满脂滴，但与来自食物喂养的对照大鼠的细胞相比，铺板效率或活力没有差异。在整个 18 小时的实验中，两组细胞以相似的速率合成和分泌免疫沉淀载脂蛋白 B 和 E。因此，膳食胆固醇对血清载脂蛋白浓度和肝细胞合成和分泌的影响之间存在不一致。数据表明，肝脏载脂蛋白合成的改变不能解释饮食胆固醇引起的血清载脂蛋白浓度的变化。
To examine the unproved hypothesis that dietary cholesterol affects the synthesis of apolipoprotein B and E, we fed rats a cholesterol-rich diet that has been shown to alter dramatically the serum concentrations of these apolipoproteins. Rats fed for 4 weeks on a cholesterol-rich diet accumulate increased concentrations of low Mr apolipoprotein B (+2.7-fold) and decreased concentrations of apolipoprotein E (-40%) in their serum. Hepatocytes obtained from similarly treated rats were placed in monolayer culture and the rate of synthesis de novo of apolipoproteins was determined. Although cells from cholesterol-fed rats remained filled with lipid droplets throughout the experimental period, there was no difference in plating efficiency or viability, compared with cells obtained from chow-fed control rats. Both groups of cells synthesized and secreted immunoprecipitable apolipoproteins B and E at similar rates throughout the 18 h experiment. Thus there was a discordance between the effects of dietary cholesterol on serum apolipoprotein concentrations and hepatocyte synthesis and secretion. The data indicate that altered hepatic apolipoprotein synthesis cannot account for the changes in serum apolipoprotein concentrations caused by dietary cholesterol.