Eriksson P O, Butler-Browne G S, Thornell L E
Department of Clinical Oral Physiology, University of Umeå, Sweden.
Muscle Nerve. 1994 Jan;17(1):31-41. doi: 10.1002/mus.880170105.
An enzyme- and immunohistochemical study has been performed on human masseter muscle spindles. Antibodies selective for different myosin heavy chain (MHC) isoforms and M-band proteins (M-protein, myomesin, and MM-CK) were used. The expression of these proteins was determined in the different intrafusal fiber types. Nuclear bag1 and nuclear bag2 fibers expressed predominantly slow-twitch and slow-tonic MHCs. The bag2 fibers in addition contained fetal MHC. Nuclear chain fibers coexpressed embryonic, fetal, and fast-twitch MHCs. The bag2 and chain fibers contained all three M-band proteins, whereas the bag1 fibers contained only myomesin. In general the MHC expression in the human masseter intrafusal fiber types was similar to that previously reported for limb muscles in man as well as for limb and masseter muscles in other species. However, the number of intrafusal fibers per spindle was unusually high (up to 36). This reinforces the idea that masseter muscle spindles have a strong proprioceptive impact during the control of jaw movements.
已对人类咬肌肌梭进行了一项酶学和免疫组织化学研究。使用了对不同肌球蛋白重链（MHC）亚型和M带蛋白（M蛋白、肌间蛋白和MM-CK）具有选择性的抗体。在不同的梭内纤维类型中测定了这些蛋白质的表达。核袋1纤维和核袋2纤维主要表达慢肌动和慢紧张型MHC。此外，核袋2纤维含有胎儿型MHC。核链纤维共同表达胚胎型、胎儿型和快肌动MHC。核袋2纤维和核链纤维含有所有三种M带蛋白，而核袋1纤维仅含有肌间蛋白。一般来说，人类咬肌梭内纤维类型中的MHC表达与先前报道的人类肢体肌肉以及其他物种的肢体和咬肌中的表达相似。然而，每个肌梭内的梭内纤维数量异常高（多达36根）。这强化了这样一种观点，即咬肌肌梭在控制下颌运动期间具有强烈的本体感受作用。
