Two-photon microscopic analysis of acetylcholine-induced mucus secretion in guinea pig nasal glands
Two-photon microscopic analysis of acetylcholine-induced mucus secretion in guinea pig nasal glands
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DOI：
10.1016/j.ceca.2004.12.003
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发表时间：
2005-04-01
期刊：
影响因子：
4
通讯作者：
Nemoto, T
中科院分区：
文献类型：
--
作者：
Oshima, A;Kojima, T;Nemoto, T
应用双光子激发成像技术研究了乙酰胆碱（ACh）诱导豚鼠鼻腺泡内游离Ca ~（2+）浓度（[Ca ~（2+）]（i））、液体分泌和胞吐的时空变化。载有荧光Ca 2+指示剂fura-2的腺泡横截面图像显示，ACh诱发的[Ca 2 +]（i）增加是立即的，并从腺泡细胞的顶端区域（分泌极）扩散到基底区域。浸泡在含有荧光极性示踪剂，磺酰罗丹明B（SR B）的溶液中的腺泡，发现液体分泌，检测到SR B荧光从细胞外空间的快速消失，只发生在腔区域，并伴随着腺泡细胞体积的减少。单个的胞吐事件也用SRB可视化为在顶膜处形成Ω形轮廓。与液体分泌的快速性相反，分泌颗粒的胞吐作用相对于[Ca 2 +]（i）的增加延迟了约70 s。胞吐事件也发生在细胞质深处，以连续的方式，与初级胞吐相比，次级胞吐的潜伏期大大减少。顺序复合胞吐相对于液体分泌的延迟对于分泌颗粒的粘性内容物释放到鼻腔中可能是重要的。(C)2005爱思唯尔有限公司保留所有权利。
The spatiotemporal changes in intracellular free Ca2+ concentration ([Ca2+](i)) as well as fluid secretion and exocytosis induced by acetylcholine (ACh) in intact acini of guinea pig nasal glands were investigated by two-photon excitation imaging. Cross-sectional images of acini loaded with the fluorescent Ca2+ indicator fura-2 revealed that the ACh-evoked increase in [Ca2+](i) was immediate and spread from the apical region (the secretory pole) of acinar cells to the basal region. Immersion of acini in a solution containing a fluorescent polar tracer, sulforhodamine B (SRB), revealed that fluid secretion, detected as a rapid disappearance of SRB fluorescence from the extracellular space, occurred exclusively in the luminal region and was accompanied by a reduction in acinar cell volume. Individual exocytic events were also visualized with SRB as the formation of Omega-shaped profiles at the apical membrane. In contrast to the rapidity of fluid secretion, exocytosis of secretory granules occurred with a delay of similar to 70 s relative to the increase in [Ca2+](i). Exocytic events also occurred deep within the cytoplasm in a sequential manner with the latency of secondary exocytosis being greatly reduced compared with that of primary exocytosis. The delay in sequential compound exocytosis relative to fluid secretion may be important for release of the viscous contents of secretory granules into the nasal cavity. (C) 2005 Elsevier Ltd. All rights reserved.