Turnover, membrane insertion, and degradation of sodium channels in rabbit urinary bladder.
Turnover, membrane insertion, and degradation of sodium channels in rabbit urinary bladder.
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兔膀胱钠通道的周转、膜插入和降解。
DOI：
10.1126/science.6612343
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发表时间：
1983
期刊：
影响因子：
--
通讯作者：
Diamond,JM
中科院分区：
文献类型：
--
作者：
Loo,DD;Lewis,SA;Ifshin,MS;Diamond,JM
兔膀胱的噪声分析揭示了两个组成部分：洛伦兹噪声，产生于阿米洛利与Na+通道的相互作用，和闪烁噪声（1/f，其中是频率），如在其他生物膜。静水压力，这导致细胞内囊泡膜和顶膜之间的交换，增加阿米洛利敏感通道的数量，但不是单通道电流。闪烁噪声来自于已经失去阿米洛利敏感性和Na+至K+选择性的退化通道。通过清洗粘膜表面选择性地去除降解的通道。这些结果意味着通道周转细胞内合成，从囊泡转移到顶端膜，降解和消除。
Noise analysis of rabbit bladder revealed two components: Lorentzian noise, arising from interaction of amiloride with the Na+channel, and flicker noise (1/f, wherefis frequency), as in other biological membranes. Hydrostatic pressure, which causes exchange between intracellular vesicular membrane and apical membrane, increases the number but not the single-channel current of the amiloride-sensitive channels. Flicker noise arises from degraded channels that have lost amiloride sensitivity and Na+to K+selectivity. The degraded channels were selectively removed by washing the mucosal surface. These results imply channel turnover by intracellular synthesis, transfer from vesicular to apical membrane, degradation, and elimination.