Molecular mechanism of adaptation in human ventricular myosin

已知肌肉收缩受细胞内Ca 2+浓度变化的调节，其可记录为各种肌肉中的Ca^<2+>瞬变。虽然记录单个肌细胞的Ca^<2+>瞬变对于阐明Ca ~（2+）引起的肌肉机械活动机制具有重要意义，但这仅可能发生在骨骼肌纤维中，在本课题的研究过程中，我们成功地利用indo-1荧光技术记录了单个心肌细胞的Ca^<2+>瞬变。我们已经发现，在等长收缩的心肌细胞和在小负荷下缩短的心肌细胞之间，Ca^<2+>瞬变存在显著差异。

Muscle contraction is known to be regulated by changes in intracellular Ca2+ concentration, which can be recorded as Ca^<2+> transients in various kinds of muscle. Although the recording of Ca^<2+> transients from a single muscle cell is informative in elucidating mechanisms of muscle mechanical activity by Ca2+, it is only possible in skeletal muscle fibers.During the course of research work in the present project, we have succeeded in recording Ca^<2+>transients from single cardiac myocytes by use of indo-1 fluorescence. We have already found a marked difference in Ca^<2+>transients between myocytes contracting isometrically and those shortening under small loads.