Kawahara H, Matsuda Y, Tsuchishima M, Wang X E, Takada A
Department of Internal Medicine, Kanazawa Medical University, Ishikawa, Japan.
Alcohol Alcohol Suppl. 1993;1A:29-35. doi: 10.1093/alcalc/28.supplement_1a.29.
The effects of ethanol and acetaldehyde on the maturation and secretion of hepatic glycoproteins in cultured rat hepatocytes were analysed using a pulse-chase labelling method and autoradiography following two-dimensional gel electrophoresis. A spot for transferrin was detected at mol. wt 77,000 and pI 5.2-5.4 on the autoradiogram in the control culture. The spot for transferrin shifted to the more basic isoforms by treatment for 3 hr with monensin or tunicamycin. The spot for transferrin also shifted to the more basic side by treatment with acetaldehyde for 3 hr or by additional treatment for 3 hr following pretreatment with ethanol for 6 hr. However, the shift of transferrin was not observed following treatment with ethanol for 3 hr. These results suggest that glycosylation of secretory glycoproteins in the Golgi apparatus is inhibited by acetaldehyde, but not by ethanol itself, and that this inhibition may play an important role in the development of alcoholic liver disease.
采用脉冲追踪标记法和二维凝胶电泳后的放射自显影技术,分析了乙醇和乙醛对培养的大鼠肝细胞中肝糖蛋白成熟和分泌的影响。在对照培养的放射自显影片上,检测到转铁蛋白在分子量77,000和等电点5.2 - 5.4处有一个斑点。用莫能菌素或衣霉素处理3小时后,转铁蛋白的斑点向更碱性的同工型移动。用乙醛处理3小时或在乙醇预处理6小时后再用乙醛处理3小时,转铁蛋白的斑点也向更碱性的方向移动。然而,用乙醇处理3小时后未观察到转铁蛋白的移动。这些结果表明,乙醛可抑制高尔基体中分泌性糖蛋白的糖基化,而乙醇本身则无此作用,且这种抑制作用可能在酒精性肝病的发生发展中起重要作用。