豚鼠耳蜗内毛细胞、外毛细胞及外指细胞钙成像

CALCIUM IMAGING OF COCHLEAR INNER AND OUTER HAIR CELLS AND DEITERS CELLS OF THE GUINEA PIGS

用ｆｌｕｏ－３／ｆｕｒａ－ｒｅｄ荧光比值作细胞内游离钙指标，用激光扫描共聚焦显微镜测定豚鼠耳蜗分离的内、外毛细胞及外指细胞的游离钙，并利用钙成像技术进行细胞形态计量。单个外毛细胞呈试管状。内毛细胞呈烧瓶状，有明显的颈部。外指细胞分为体部及指状突部。毛细胞的胞内游离钙浓度明显高于外指细胞。毛细胞的胞质、胞核及表皮板的游离钙浓度不同。外指细胞的细胞体与指状突的游离钙浓度也不同。本研究认为，有无颈部为区别分离的内、外毛细胞的重要标准，外指细胞可凭借其特异的指状突结构以资识别。内耳毛细胞及外指细胞胞内游离钙分布的不均一性可能与各部位生理功能不同有关。

The calcium imaging of cochlear inner and outer hair cells (IHC and OHC) and Deiters cells of guinea pigs was investigated using laser scanning confocal microscopy and fluo 3 and fura red fluorescence ratios. The OHC is cylindrical in shape. Its length is between 53 4-83 3 μm. The IHC has a distinctive neck and its length is 36 8±1 9 μm. The Deiters cell is divided into body and phalangeal prominence. The calcium distribution among the cytosol, nucleus and cuticular plate in hair cells was different, and it was also different between body and phalangeal prominence in Deiters cells. Ca 2+ concentration in hair cells is higher than that in Deiterss cells. This phenomenon may indicate that these dissimilarifies are related to their different physiological roles. A remarkable criterion for distinguishing isolated IHCs from OHCs is that the former has a distinctive neck but the latter has none. The Deiters cell can be identified by its peculiar phalangeal prominence.