ION CHANNELS IN PANCREATIC CELLS

描述：这个应用程序探索刺激-分泌耦合在 胰腺的胰岛细胞。调查员假设 胰岛素颗粒的一个亚群与 质膜中的Ca~(2+)通道，这些颗粒在 对局部钙离子浓度升高的反应。特定目标测试 对这种共同本地化模式的四个预测：1)版本应该有一个 与总钙离子进入的独特关系应独立于 启动进入的条件；2)广泛分离的去极化 应以不同的潜伏期激发胰岛素释放；3)持续 进入Ca2+应该会耗尽共局域化的颗粒池，导致 在该池被补充时的静止期；以及4)满足以下条件的条件 增加共同本地化池的大小应允许长时间的 分泌物。为了评估这些预测，调查人员将使用 能够测量这些刺激和参数的仪器 单个β细胞同时分泌。

DESCRIPTION: This application explores stimulation-secretion coupling in the beta islet cells of the pancreas. The investigator has hypothesized that a subpopulation of insulin granules are 'loosely co-localized' with Ca2+ channels in the plasmalemma, and these granules are released rapidly in response to local increases in Ca2+ concentration. The specific aims test four predictions of this co-localization model: 1) release should have a distinctive relationship to total Ca2+ entry that should be independent of the conditions initiating that entry; 2) widely-separated depolarizations should evoke insulin release with distinct latency periods; 3) sustained Ca2+ entry should deplete the co-localized pool of granules, resulting in a period of quiescence while that pool is replenished; and 4) conditions that increase the size of the co-localized pool should permit prolonged bouts of secretion. To evaluate these predictions, the investigator will use instrumentation capable of measuring these parameters of stimulation and secretion simultaneously in single beta cells.