Induction of Cytosolic Triiodo-L-Thyronine (T3) Binding Protein (CTBP) by T3 in Primary Cultured Rat Hepatocytes

Endocrine Journal

AKIHIRO SAKURAI¹  TAKESHI NAGASAWA¹  KIYOSHI HASHIZUME¹  HIROAKI KOBAYASHI¹  KAZUO ICHIKAWA¹  MIYUKI KATAI¹  MUTSUHIRO KOBAYASHI¹  TEIJI TAKEDA¹  YUTAKA NISHII¹ 

[1] Department of Geriatrics, Endocrinology and Metabolism, Shinshu University School of Medicine

关键词: Rat hepatocytes;    Triiodothyronine (T3);    Cytosolic T3 Binding Protein (CTBP);    Malic enzyme;   

DOI  :  10.1507/endocrj.40.399

学科分类：内分泌与代谢学

来源: Japan Endocrine Society

【 摘 要 】

References(19)Cited-By(4)Cytosolic 3, 5, 3'-triiodo-L-thyronine (T3)-binding protein (CTBP) plays an important role in the regulation of intracellular T3 translocation from cytoplasm to the nuclear T3 receptor. We examined whether the CTBP activity could be induced by T3 or not in cultured hepatocytes prepared from thyroidectomized rats. CTBP activity was not detected in primary cultured hepatocytes from thyroidectomized rats. However, the protein was induced by the addition of T3 to the culture medium. The increase in the activity of CTBP was time dependent and the maximal level was obtained by 48h in the presence of 300nM T3. CTBP activity was also increased by retinol (35μM) or by 1, 25-(OH)2-vitamin D3 (10nM). On the other hand, the activity of malic enzyme (ME) was induced by the addition of T3 to the culture medium. The maximal activity of ME was obtained by 48h in the presence of 300nM T3. The increase in ME activity was also induced by retinol or 1, 25-(OH)2-vitamin D3. These results suggested that not only ME activity but also CTBP activity is induced by T3. Further, retinol and vitamin D3 have similar effects on the induction of CTBP activity and ME activity.

【 授权许可】

Unknown