Hietanen-Peltola M, Pelto-Huikko M, Rechardt L, Hökfelt T
Department of Biomedical Sciences, University of Tampere, Finland.
Histochem J. 1992 Sep;24(9):673-8. doi: 10.1007/BF01047588.
Calbindin D-28k-immunoreactivity has been demonstrated in some of the intrafusal muscle fibres and in the capsule of adult rat muscle spindles. In this study, the immunocytochemical localization of calbindin D-28k in the muscle spindles of triceps surae muscle was studied during postnatal maturation and after denervation. In young rats calbindin D-28k-immunoreactivity was seen in a few intrafusal fibres, first at the age of 4 days. At the 7th day, three calbindin D-28k-immunoreactive fibres and one unlabelled fibre were seen in most muscle spindles, as in adult rats. The spindle capsule and perineurial sheath of nerves were first seen to exhibit calbindin D-28k immunoreactivity at the age of 14 days, and thereafter the localization of calbinding D-28k-like immunoreactivity was similar to that in adult rats. After denervation, calbindin D-28k-immunoreactivity remained in intrafusal muscle fibres and the spindle capsule for a long period. After two months of denervation, calbindin D-28k immunoreactivity could still be seen in the spindle capsule, but the intrafusal fibres were not labelled. The innervation is known to have trophic effects on the intrafusal fibres. The present findings suggest that the expression of calbindin D-28k-immunoreactivity in maturating muscle spindles may be induced by the developing innervation. The decrease of calbindin D-28k-immunoreactivity in intrafusal fibres after denervation may be due to the loss of trophic factors released by the nerves.
在成年大鼠肌梭的一些梭内肌纤维和被膜中已证实有钙结合蛋白D-28k免疫反应性。在本研究中，对腓肠肌肌梭中钙结合蛋白D-28k在出生后成熟过程及去神经支配后的免疫细胞化学定位进行了研究。在幼鼠中，4日龄时首次在少数梭内纤维中见到钙结合蛋白D-28k免疫反应性。7日龄时，在大多数肌梭中可见到三条钙结合蛋白D-28k免疫反应性纤维和一条未标记的纤维，与成年大鼠一样。神经的梭外被膜和神经束膜在14日龄时首次显示出钙结合蛋白D-28k免疫反应性，此后钙结合蛋白D-28k样免疫反应性的定位与成年大鼠相似。去神经支配后，钙结合蛋白D-28k免疫反应性在梭内肌纤维和梭外被膜中长时间留存。去神经支配两个月后，仍可在梭外被膜中见到钙结合蛋白D-28k免疫反应性，但梭内纤维未被标记。已知神经支配对梭内纤维有营养作用。目前的研究结果表明，在成熟的肌梭中钙结合蛋白D-28k免疫反应性的表达可能是由发育中的神经支配诱导的。去神经支配后梭内纤维中钙结合蛋白D-28k免疫反应性的降低可能是由于神经释放的营养因子丧失所致。
