Phospholipase C (PLC)β has a role in saliva secretion by controlling intracellular Ca2+via its product, IP3. The present study was attempted to localize PLCβ isoforms in mouse salivary glands in situ. A single major band was detected for PLCβ3 in immunoblots of the parotid and sublingual glands (PG, SLG), while no such band was seen in the submandibular gland (SMG). No bands were detected for PLCβ1 or 4 in the three glands. In immuno-light microscopy of PG and SLG, substantial immunoreactivity for PLCβ3 was seen in the cytoplasm including the plasmalemma of almost all ductal cells, while no distinct immunoreactivity was discerned in most acinar cells except for sublingual demilune cells. Numerous ductal cells exhibited higher immunoreactivity for PLCβ3 in their apical/supranuclear cell domain including the plasmalemma than in the basal/infranuclear domain, indicating an apico-basal polarity. In immuno-gold electron microscopy of PG ducts and SLG ducts and demilunes, most gold particles were found in association with plasma membranes as well as various intracellular membranes, most of which formed small oblong or flattened vesicles and vacuoles. A few particles were seen without association with any membranous structures. The present finding supports the previous physio-pharmacological result that Ca2+-signaling proteins as well as initial intracellular Ca2+ changes occur in the apical cell domain including the plasma membranes of the exocrine cells.

中文翻译：

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磷脂酶Cβ3在成年小鼠主要唾液腺中的定位。

磷脂酶C（PLC）β通过其产品IP3控制细胞内Ca2 +，从而在唾液分泌中发挥作用。本研究试图在小鼠唾液腺中原位定位PLCβ同工型。在腮腺和舌下腺（PG，SLG）的免疫印迹中检测到一条单一的PLCβ3主谱带，而在下颌下腺（SMG）中未发现该主谱带。在三个腺体中未检测到PLCβ1或4的条带。在PG和SLG的免疫光镜检查中，在包括几乎所有导管细胞的浆膜的细胞质中，对PLCβ3具有实质性的免疫反应性，而在大多数腺泡细胞中，除了舌下半抗原细胞，没有发现明显的免疫反应性。许多导管细胞在其顶质/上核细胞结构域（包括质膜）中对PLCβ3的免疫反应性高于在基体/核仁结构域中，这表明其呈apico-基础极性。在PG导管，SLG导管和半胱氨酸的免疫金电子显微镜检查中，发现大多数金颗粒与质膜以及各种细胞内膜相关，其中大多数形成小的椭圆形或扁平囊泡和液泡。看到一些颗粒与任何膜结构无关。本发现支持先前的生理-药理学结果，即在包括外分泌细胞质膜的根尖细胞域中发生了Ca2 +信号蛋白以及初始细胞内Ca2 +变化。在PG导管，SLG导管和半胱氨酸的免疫金电子显微镜检查中，发现大多数金颗粒与质膜以及各种细胞内膜相关，其中大多数形成小的椭圆形或扁平囊泡和液泡。看到一些颗粒与任何膜结构无关。本发现支持先前的生理-药理学结果，即在包括外分泌细胞质膜的顶细胞域中发生了Ca2 +信号蛋白以及初始细胞内Ca2 +变化。在PG导管，SLG导管和半胱氨酸的免疫金电子显微镜检查中，发现大多数金颗粒与质膜以及各种细胞内膜相关，其中大多数形成小的椭圆形或扁平囊泡和液泡。看到一些颗粒与任何膜结构无关。本发现支持先前的生理-药理学结果，即在包括外分泌细胞质膜的根尖细胞域中发生了Ca2 +信号蛋白以及初始细胞内Ca2 +变化。看到一些颗粒与任何膜结构无关。本发现支持先前的生理-药理学结果，即在包括外分泌细胞质膜的根尖细胞域中发生了Ca2 +信号蛋白以及初始细胞内Ca2 +变化。看到一些颗粒与任何膜结构无关。本发现支持先前的生理-药理学结果，即在包括外分泌细胞质膜的根尖细胞域中发生了Ca2 +信号蛋白以及初始细胞内Ca2 +变化。