Jeejeebhoy K N, Phillips M J, Bruce-Robertson A, Ho J, Sodtke U
Biochem J. 1972 Mar;126(5):1111-24. doi: 10.1042/bj1261111.
Decrease of absolute synthesis of albumin and fractional synthesis of transferrin was observed within 3h of orally administering ethanol (4ml/kg) to rats maintained on a 40%-protein diet. In contrast, absolute synthesis of fibrinogen was unaffected. With this ethanol intake, the changes in protein synthesis occurred without significant ultrastructural change in the liver. When the ethanol intake was greater (8ml/kg) ultrastructural disruption was observed. However, both the decrease of plasma protein synthesis and the ultrastructural alterations could be prevented by the simultaneous administration of a mixture of amino acids with the ethanol. The latter findings, not reported hitherto, suggest that ethanol may interfere with hepatic plasma protein synthesis and ultrastructure more through a disturbance of amino acid metabolism than through direct physical damage to the hepatocyte. An Appendix outlines the deconvolutional method used to correct for losses of labelled protein in the period during which measurements were made. The principle may also be applied to labelled plasma urea. The details of the calculations are given in a supplementary paper that has been deposited as Supplementary Publication 50007 at the National Lending Library for Science and Technology, Boston Spa, Yorks. LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1972) 126, 5.
给维持40%蛋白质饮食的大鼠口服乙醇(4毫升/千克)后3小时内,观察到白蛋白绝对合成量减少,转铁蛋白合成分数下降。相比之下,纤维蛋白原的绝对合成未受影响。摄入这种乙醇量时,肝脏蛋白质合成发生变化,但超微结构无明显改变。当乙醇摄入量增加(8毫升/千克)时,可观察到超微结构破坏。然而,同时给予氨基酸混合物与乙醇可防止血浆蛋白质合成减少和超微结构改变。后一迄今未报道的发现表明,乙醇可能更多地通过干扰氨基酸代谢而非直接对肝细胞造成物理损伤来干扰肝脏血浆蛋白质合成和超微结构。附录概述了用于校正测量期间标记蛋白质损失的去卷积方法。该原理也可应用于标记血浆尿素。计算细节见一篇补充论文,该论文已作为补充出版物50007存放在英国约克郡波士顿温泉市国家科技出借图书馆,邮编LS23 7BQ,可按《生物化学杂志》(1972年)126卷5期所示条件从该处获取复印件。