Yarom R, Sherman Y, Sagher U, Peled I J, Wexler M R, Gorodetsky R
J Neurol Sci. 1987 Jul;79(3):315-26. doi: 10.1016/0022-510x(87)90238-3.
X-ray spectrometry was used to measure the concentrations of calcium, iron, copper and zinc in tongue muscles from patients with Down's syndrome (DS) undergoing partial glossectomy. Similar measurements on samples from autopsies served as controls. Electron microscopy was used to examine neuromuscular junctions. The calcium and copper were significantly elevated and correlated in DS while the iron and zinc showed little change. The copper increase is probably connected with the known high level of Zn-Cu superoxide dismutase (SOD), coded for by chromosome 21. (In DS there is a trisomy 21). The excess of SOD may interfere with free radicals needed for excitation-contraction coupling and may be instrumental in damaging junctional membranes. The high calcium may result from such membrane damage. It is suggested that neuromuscular junction pathology, either genetic or free radical induced, may cause the tongue weakness in DS.
采用X射线光谱法测量了接受部分舌切除术的唐氏综合征（DS）患者舌肌中钙、铁、铜和锌的浓度。对尸检样本进行的类似测量作为对照。使用电子显微镜检查神经肌肉接头。DS患者的钙和铜显著升高且呈正相关，而铁和锌变化不大。铜含量的增加可能与已知的由21号染色体编码的高水平锌铜超氧化物歧化酶（SOD）有关。（DS患者存在21号染色体三体）。过量的SOD可能会干扰兴奋-收缩偶联所需的自由基，并可能导致连接膜受损。高钙可能是这种膜损伤的结果。有人认为，无论是遗传因素还是自由基诱导的神经肌肉接头病变，都可能导致DS患者的舌肌无力。
