Organ Cell Biology of Salivary Secretion: Integrated analyses by combined approaches

器官是一群具有不同形态和功能特性的不同细胞，但它可以表现为一个完整的整体。这项研究的目的是澄清确保各机构获得协调职能的结构基础。唾液腺的功能主要是由分隔的上皮域、腺泡和导管实现的，这些上皮域、腺泡和导管也表现出特有的形态特化。高速共聚焦显微镜显示腺泡和导管之间有明显的钙信号模式。腺泡中的细胞是同步反应的，而导管中的细胞是异步反应的。缝隙连接分子Cx32主要分布在腺泡细胞之间，因此唾液腺中的钙信号系统是根据组织结构特异性地构建的。β-半乳糖苷酶基因敲除小鼠在腺泡区和颗粒管区出现空泡结构。一只患有甲状腺功能减退症的大鼠，表现出颗粒管段的缺失。β-半乳糖苷酶和甲状腺素被认为在腺泡和导管的形态发生中起重要作用。我的结论是，节段性上皮细胞分化在控制协调的器官功能中起着基础性的作用。

An organ is a mass of diverse cells possessing various morphological and functional identities, yet it can behave as an integrated unity. This study was aimed to clarify the structural bases that ensure organs to acquire the harmonized function. Salivary gland function is primarily achieved by the compartmentalized epithelial domains, acini and ducts, which also exhibit characteristic morphological specialization. High-speed confocal microscopy showed distinct pattern of calcium signaling between acini and ducts. Cells in acini responded synchronously while those in ducts responded asynchronously. A gap junction molecule, connexin 32, was immunolocalized predominantly between the acinar cells; thus the calcium signaling system in salivary glands is constructed specifically according to the tissue architecture. Beta-galactosidase knock-out mice revealed the appearance of vacuolar structures in the acinar domain and the granulated duct domain. A rat with hypothyroydism, rdw, exhibited the lack of the granulated duct segment. Beta-galactosidase and thyroxine are considered to play significant roles in the morphogenesis of acinar and duct segments. I was concluded that the segment specific differentiation of epithelia plays fundamental roles in controlling the harmonized organ function.