期刊名称：Journal of Nutritional Science and Vitaminology
印刷版ISSN：0301-4800
电子版ISSN：1881-7742
出版年度：1998
卷号：44
期号：6
页码：799-807
DOI：10.3177/jnsv.44.799
出版社：Center for Academic Publications Japan
摘要：The effects of thyroxine (T4) and triiodothyronine (T3) on growth, muscle protein degradation, and proteases activities in cultured chick muscle cells were studied. The cells were treated with a physiological level of T4 (60ng/mL) or T3 (12ng/mL) for 6d. Calpain, cathepsins, and proteasome activities and N τ-methylhistidine release were measured as indexes of myofibrillar protein breakdown. Creatine kinase activity was also measured as an index of myotube formation. Calpain activity was increased by T4 and T3. Cathepsin D and proteasome activities and N τ-methylhistidine release were increased by T3, but not by T4. Neither were cathepsin B and B+L activities affected by T3 or T4. Creatine kinase activity was increased by T4 and T3. The results suggest that myotube formation is accelerated by T4 and T3, whereas myofibrillar protein degradation is accelerated by T3, but not by T4.
