Princen J M, Mol-Backx G P, Yap S H
Biochim Biophys Acta. 1981 Sep 28;655(2):119-27. doi: 10.1016/0005-2787(81)90001-0.
Controversial results have been reported in the last few years concerning the effects of ethanol on hepatic protein synthesis. In most of the studies no distinction has been made between the synthetic capabilities of the polyribosomes and the secretory product of labelled protein by the hepatocytes. In order to assess the influence of a single feeding of ethanol on the synthesis of albumin and total protein by the polyribosomes of rat liver, free and membrane-bound polyribosomes were isolated quantitatively from rats given 4--8 g ethanol per kg body weight 3--5 h before killing. The following results were obtained: (1) No difference was found in yield and size of free and membrane-bound polyribosomes isolated from control and ethanol-treated rats. The abilities to synthesize albumin and total protein were also equal for polyribosomes from both groups. (2) Addition of 1% ethanol to the incubation mixture of protein synthesis lowered albumin and total protein synthesis by 20%. No effect was observed with 0.5% ethanol. (3) Cell sap prepared from ethanol-treated rats contains a factor or factors which stimulate protein synthesis (10--15%). (4) The albumin mRNA sequence content was not changed in free and membrane-bound polyribosomal RNA fractions of ethanol-treated rats as compared to the control animals.
在过去几年里，关于乙醇对肝脏蛋白质合成的影响，已有一些有争议的研究结果报道。在大多数研究中，并未区分多核糖体的合成能力与肝细胞标记蛋白质的分泌产物。为了评估单次喂食乙醇对大鼠肝脏多核糖体合成白蛋白和总蛋白的影响，在处死前3至5小时，给每千克体重给予4 - 8克乙醇的大鼠定量分离游离和膜结合多核糖体。得到以下结果：（1）从对照大鼠和乙醇处理大鼠中分离出的游离和膜结合多核糖体的产量和大小没有差异。两组多核糖体合成白蛋白和总蛋白的能力也相同。（2）在蛋白质合成的孵育混合物中添加1%乙醇可使白蛋白和总蛋白合成降低20%。0.5%乙醇未观察到影响。（3）从乙醇处理大鼠制备的细胞液含有一种或多种刺激蛋白质合成的因子（10 - 15%）。（4）与对照动物相比，乙醇处理大鼠的游离和膜结合多核糖体RNA组分中的白蛋白mRNA序列含量没有变化。
