Bucki R, Górska M, Zendzian-Piotrowska M, Górski J
Department of Physiology, Medical School of Białystok, Poland.
J Physiol Pharmacol. 2000 Sep;51(3):535-40.
The aim of the present study was to examine the effect of triiodothyronine (T3) on the content of phospholipids and on the incorporation of blood-borne palmitic acid into the phospholipid moieties in the nuclei of the rat liver. T3 was administered daily for 7 days, 10 microg x 100 g(-1). The control rats were treated with saline. Each rat received 14C-palmitic acid, intravenously suspended in serum. 30 min after administration of the label, samples of the liver were taken. The nuclei were isolated in sucrose gradient. Phospholipids were extracted from the nuclei fraction and from the liver homogenate. They were separated into the following fractions: sphingomyelin, phosphatidylcholine, phosphatidylserine, phosphatidylinositol, phosphatidylethanolamine and cardiolipin. The content and radioactivity of each fraction was measured. It was found that treatment with T3 reduced the content of phosphatidylinositol and increased the content of cardiolipin in the nuclear fraction. In the liver homogenate, the content of phosphatidylinositol decreased and the content of phosphatidylethanolamine and cardiolipin increased after treatment with T3. The total content of phospholipids after treatment with T3 remained unchanged, both in the nuclear fraction and in the liver homogenate. T3 reduced the specific activity of phosphatidylcholine, phosphatidylserine, phosphatidylethanolamine and cardiolipin and had no effect on the specific activity of sphingomyelin and phosphatidylinositol both in the fraction of the nuclei and the liver homogenate. It is concluded that excess of triiodothyronine affects the content of phospholipids in the nuclei. The changes in the content of phospholipids in the nuclei largely reflect changes in their content in the liver.
本研究的目的是检测三碘甲状腺原氨酸（T3）对大鼠肝细胞核中磷脂含量以及血源性棕榈酸掺入磷脂部分的影响。连续7天每天给予T3，剂量为10μg×100g⁻¹。对照大鼠用生理盐水处理。每只大鼠静脉注射悬浮于血清中的¹⁴C-棕榈酸。给予标记物30分钟后，采集肝脏样本。在蔗糖梯度中分离细胞核。从细胞核部分和肝脏匀浆中提取磷脂。将它们分离成以下部分：鞘磷脂、磷脂酰胆碱、磷脂酰丝氨酸、磷脂酰肌醇、磷脂酰乙醇胺和心磷脂。测量每个部分的含量和放射性。结果发现，用T3处理可降低细胞核部分中磷脂酰肌醇的含量并增加心磷脂的含量。在肝脏匀浆中，用T3处理后磷脂酰肌醇的含量降低，磷脂酰乙醇胺和心磷脂的含量增加。用T3处理后，细胞核部分和肝脏匀浆中磷脂的总含量均保持不变。T3降低了细胞核部分和肝脏匀浆中磷脂酰胆碱、磷脂酰丝氨酸、磷脂酰乙醇胺和心磷脂的比活性，对鞘磷脂和磷脂酰肌醇的比活性没有影响。得出的结论是，过量的三碘甲状腺原氨酸会影响肝细胞核中磷脂的含量。细胞核中磷脂含量的变化在很大程度上反映了肝脏中磷脂含量的变化。
