Mølstad P, Bøhmer T, Hovig T
Biochim Biophys Acta. 1978 Oct 4;512(3):557-65. doi: 10.1016/0005-2736(78)90165-7.
L-Carnitine is actively transported into Girardi human heart cells, an established cell line from human heart. The present study was undertaken to investigate the effect of different concentrations of L-Carnitine in the growth medium on the rate of uptake of L-[3H] carnitine. Increasing the concentration of L-Carnitine from 2 to 100 mumol/l in the growth medium of cells, increased the rate of uptake of L-[3H] carnitine by about 50%. The maximal effect was reached after approx. 72 h incubation. The increase in rate seemed to be caused by synthesis of increased number of carriers, as judged by the increase of V with unchanged apparent Km for the transport process. This effect of L-carnitine could be inhibited by cycloheximide, indicating the dependence on intact protein synthesis. The morphology of the cells was studied by electron microscopy. No myofilaments were found, thus the cells are dedifferentiated and no longer typical muscular cells.
左旋肉碱可被主动转运至吉拉尔迪人心肌细胞（一种源自人心肌的成熟细胞系）中。本研究旨在探究生长培养基中不同浓度的左旋肉碱对L-[3H]肉碱摄取速率的影响。在细胞生长培养基中，将左旋肉碱的浓度从2微摩尔/升提高至100微摩尔/升，可使L-[3H]肉碱的摄取速率提高约50%。在孵育约72小时后达到最大效应。从转运过程中表观Km不变而V增加来判断，摄取速率的增加似乎是由于载体数量增加所致。左旋肉碱的这种作用可被环己酰亚胺抑制，这表明其依赖于完整的蛋白质合成。通过电子显微镜研究细胞形态。未发现肌丝，因此这些细胞已去分化，不再是典型的肌肉细胞。
