Koda M, Murawaki Y, Hirayama C
Second Department of Internal Medicine, Tottori University, School of Medicine, Yonago, Japan.
Biochem Pharmacol. 1990 Jun 15;39(12):2015-7. doi: 10.1016/0006-2952(90)90623-s.
To clarify the significance of free and small peptide-bound hydroxyproline synthesis in ethanol-induced liver injury, we measured the in vitro synthesis of [14C]hydroxyproline in the 67% ethanol-soluble fraction in rat liver slices, together with hepatic protein-bound [14C]hydroxyproline synthesis. The synthesis of free and small peptide-bound [14C]hydroxyproline was 11.1 +/- 2.0 dpm x 10(-4)/g liver/3 hr and the synthesis of protein-bound [14C]hydroxyproline was 10.1 +/- 3.3 dpm x 10(-4)/g liver/3 hr in control rat liver. In the ethanol-fed rat liver, the synthesis of free and small peptide-bound [14C]hydroxyproline significantly increased 1.5-fold and the synthesis of protein-bound [14C]hydroxyproline significantly increased 1.6-fold, while the hepatic collagen content did not change. There was a significant correlation between free and small peptide-bound [14C]hydroxyproline synthesis and protein-bound [14C]hydroxyproline synthesis. These results suggest that free and small peptide-bound hydroxyproline synthesis plays an important role in regulating the content of hepatic collagens.
为阐明游离及小肽结合型羟脯氨酸合成在乙醇诱导的肝损伤中的意义，我们测定了大鼠肝切片中67%乙醇可溶部分的[14C]羟脯氨酸体外合成，以及肝蛋白结合型[14C]羟脯氨酸的合成。对照大鼠肝脏中，游离及小肽结合型[14C]羟脯氨酸的合成量为11.1±2.0 dpm×10(-4)/g肝脏/3小时，蛋白结合型[14C]羟脯氨酸的合成量为10.1±3.3 dpm×10(-4)/g肝脏/3小时。在乙醇喂养的大鼠肝脏中，游离及小肽结合型[14C]羟脯氨酸的合成显著增加了1.5倍，蛋白结合型[14C]羟脯氨酸的合成显著增加了1.6倍，而肝脏胶原含量未发生变化。游离及小肽结合型[14C]羟脯氨酸合成与蛋白结合型[14C]羟脯氨酸合成之间存在显著相关性。这些结果表明，游离及小肽结合型羟脯氨酸合成在调节肝脏胶原含量方面起重要作用。
