期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1978
卷号：75
期号：1
页码：520-523
DOI：10.1073/pnas.75.1.520
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The mean channel open time and metabolic stability of acetylcholine receptors were studied in developing chick muscle fibers in vitro. Analysis of acetylcholine noise recorded from small patches of surface membrane on uninnervated myotubes indicates that the mean ionic channel open time is independent of receptor density. On myotubes innervated in vitro by spinal cord neurons, the mean open time of synaptic receptors was identical to that of extrasynaptic receptors on the same fibers. Receptor stability was estimated by autoradiography of cultures labeled with 125I-labeled alpha-bungarotoxin. Synaptic and extrasynaptic toxin--receptor complexes disappear at the same, relatively rapid rate. Both the mean channel open time and the apparent rate of receptor degradation are comparable to values obtained at extrasynaptic sites on denervated adult muscles in other species.
