Smith M E, Hughes S
Department of Physiology, Medical School, University of Birmingham, Edgbaston, UK.
J Neurol Sci. 1994 Jul;124 Suppl:56-8. doi: 10.1016/0022-510x(94)90178-3.
The pro-opiomelanocortin-derived peptides, beta-endorphin (beta-EP), ACTH and alpha-MSH act in concert to promote synaptogenesis and nerve growth in the neuromuscular system. Immunocytochemistry was used to detect the peptides in triceps muscles of normal developing and adult mice and in adult wobbler mice with motor neurone disease. Immunoreactivity for beta-EP and alpha-MSH/ACTH was present in some intramuscular motor nerves. There was a significantly higher proportion of immunoreactive nerves in the muscles of the developing and the diseased mice than in the normal adults. ACTH and beta-EP receptors were revealed using autoradiography. Specific binding sites for 125I-labelled ACTH and 125I-labelled beta-EP were present in some fibres in all muscles examined. There were significantly higher proportions of fibres exhibiting specific beta-EP and specific ACTH binding sites in the muscles of the developing and the diseased mice compared to the muscles of normal adults. It seems likely that the high incidence of immunoreactive nerves and of muscle fibres with the peptide receptors in the developing and diseased mice reflects the trophic actions of the peptides in the neuromuscular system.
源自阿片促黑皮质素原的肽类，如β-内啡肽（β-EP）、促肾上腺皮质激素（ACTH）和α-黑素细胞刺激素（α-MSH）协同作用，促进神经肌肉系统中的突触形成和神经生长。采用免疫细胞化学方法检测正常发育小鼠、成年小鼠以及患有运动神经元疾病的成年震颤小鼠肱三头肌中的这些肽类。在一些肌内运动神经中存在β-EP和α-MSH/ACTH的免疫反应性。与正常成年小鼠相比，发育中小鼠和患病小鼠肌肉中免疫反应性神经的比例显著更高。利用放射自显影术揭示了ACTH和β-EP受体。在所检查的所有肌肉的一些纤维中存在125I标记的ACTH和125I标记的β-EP的特异性结合位点。与正常成年小鼠的肌肉相比，发育中小鼠和患病小鼠的肌肉中呈现特异性β-EP和特异性ACTH结合位点的纤维比例显著更高。发育中小鼠和患病小鼠中免疫反应性神经和带有肽受体的肌纤维的高发生率，似乎反映了这些肽在神经肌肉系统中的营养作用。
