小牛甲状腺中碘脂质的生物合成与调节

Biosynthesis and regulation of iodolipids in calf thyroid.

作者信息

Chazenbalk G D, Pisarev M A, Juvenal G J, Kleiman de Pisarev D L, Mercuri H, De Tomás M

出版信息

Acta Endocrinol (Copenh). 1985 Jan;108(1):72-8. doi: 10.1530/acta.0.1080072.

DOI:10.1530/acta.0.1080072

Abstract

The incorporation of 125I into iodolipids was investigated in calf thyroid slices. Time course studies showed that the iodination of lipid reaches a plateau after 30 min of incubation. A highly significant correlation was found between iodination of lipid and of protein (r = 0.906), suggesting that both reactions may be related. Addition of PTU or MMI caused a significant inhibition of lipid iodination, indicating that a peroxidase could be involved in this reaction. The iodinated lipids are not attached to protein, since they migrated in BEA chromatography and pancreatin digestion of the samples did not modify the percentage radioactivity. The iodolipid fraction observed in BEA chromatography was eluted and analysed by TLC. Iodinated free fatty acids and neutral lipids comprised most of the radioactivity. Although iodolipids are present in every subcellular fraction, the 20 000 X g pellet had the greatest proportion of iodinated fatty acids and neutral lipids.

摘要

在小牛甲状腺切片中研究了¹²⁵I掺入碘脂的情况。时间进程研究表明，脂质碘化在孵育30分钟后达到平台期。发现脂质碘化与蛋白质碘化之间存在高度显著的相关性（r = 0.906），这表明这两个反应可能相关。加入丙硫氧嘧啶（PTU）或甲巯咪唑（MMI）会显著抑制脂质碘化，表明过氧化物酶可能参与此反应。碘化脂质不与蛋白质结合，因为它们在硼酸乙酯（BEA）色谱中迁移，并且样品经胰蛋白酶消化后放射性百分比没有改变。对在BEA色谱中观察到的碘脂部分进行洗脱并通过薄层色谱（TLC）分析。碘化游离脂肪酸和中性脂质占大部分放射性。尽管碘脂存在于每个亚细胞组分中，但20000×g沉淀中碘化脂肪酸和中性脂质的比例最大。