The effects of electrical inactivity and denervation on the distribution of acetylcholine receptors in developing rat muscle.
The effects of electrical inactivity and denervation on the distribution of acetylcholine receptors in developing rat muscle.
复制标题
电不活动和去神经支配对发育中的大鼠肌肉中乙酰胆碱受体分布的影响。
DOI：
10.1016/0012-1606(82)90224-x
复制
发表时间：
1982
影响因子：
2.7
通讯作者：
Bennett,JI
中科院分区：
文献类型：
--
作者：
Ziskind-Conhaim,L;Bennett,JI
大鼠胚胎胸腔体壁的外植体，包括肋间肌、肋骨和邻近的脊髓节段，均维持在器官培养中。神经肌肉分化在培养物中进行，其模式和时间过程与子宫内发育的相同突触相似。为了进一步了解调节大鼠肌管发育中乙酰胆碱敏感性的因素，我们研究了电不活动和去神经支配对乙酰胆碱受体分布的影响。当肌肉和脊髓在妊娠 15 天时被移植时，在连接受体簇出现之前，需要完整的神经末梢来启动神经-肌肉连接处的受体聚集。电活动对于诱导这些初级连接簇不是必需的。然而，不活动导致沿着纤维的随机位点出现次级多重受体簇。在河豚毒素存在的情况下，不活跃的神经末梢会发芽。这伴随着终板处的连接受体簇的增大，但神经萌芽和连接外受体聚集体的位置之间没有相关性。在发育后期，当连接受体代谢更加稳定时，末端发芽未能诱导连接受体聚集体大小的增加。
Explants of thoracic body wall from rat embryos, including intercostal muscles, ribs, and the adjacent segments of spinal cord, were maintained in organ culture. Nerve-muscle differentiation proceeded in culture with a pattern and time course similar to that of the same synapses developingin utero. To understand further the factors that regulate acetylcholine sensitivity in developing rat myotubes, we studied the effects of electrical inactivity and denervation on the distribution of acetylcholine receptors. When muscle and spinal cord were explanted at 15 days of gestation, prior to the appearance of junctional receptor clusters, intact nerve terminals were required to initiate receptor aggregation at the site of nerve-muscle junction. Electrical activity was not necessary for induction of these primary junctional clusters. Inactivity resulted, however, in the appearance of secondary multiple receptor clusters at random sites along the fibers. In the presence of tetrodotoxin, the electrically inactive nerve terminals sprouted; this was accompanied by the enlargement of the junctional receptor clusters, at the end plate, but there was no correlation between nerve sprouting and the location of extrajunctional receptor aggregates. Later in development, at a time when the junctional receptors are metabolically more stable, terminal sprouting failed to induce the increase in size of junctional receptor aggregates.