Functional and morphological analysis of the main excretory duct epithelium of rat submandibular gland. -VII Molecular biological study of the main excretory duct-

本研究旨在阐明大鼠（9周龄雄性Wistar大鼠）下颌下腺主要排泄管的功能。2003- 2005年取得以下结果：1.应用免疫细胞化学方法对大鼠下颌下腺主要排泄管上皮细胞中与味觉信号转导和离子通道有关的GTP结合蛋白G α gustducin和G α O的定位进行了研究电镜下可见G α gustducin免疫反应阳性细胞主要分布于毛簇细胞和II型光细胞。在簇状细胞中，免疫金颗粒存在于微绒毛上和靠近顶端囊泡。在光细胞II型，管腔表面和囊泡下的管腔与免疫金颗粒反应。从MED中提取的总RNA经RT-PCR检测，显示与成熟（剪接）的α gustducin mRNA相对应的阳性条带。旋转中存在信号 ...更多信息 用地高辛标记的反义核酸探针进行原位杂交，在除构成主要排泄管的基底细胞外的所有细胞类型中均观察到G α O免疫反应阳性。尤其是簇状细胞和II型光细胞的免疫反应性较强。除了G α gustducin免疫反应性外，免疫金颗粒还存在于簇细胞的微绒毛和顶囊附近，以及II型轻细胞的腔表面和腔下方的囊泡。从MED中提取的总RNA经RT-PCR检测显示与成熟（剪接）α O mRNA相对应的阳性条带。用地高辛标记的反义核酸探针进行原位杂交，除基底细胞外，所有细胞类型均出现信号。2.用免疫细胞化学方法（光镜和电镜）检测慢性酸中毒和慢性水肿时H^+/K^+ ATP酶的变化。对照组H^+/K^+ ATP酶免疫反应主要分布于细胞内。慢性代谢性酸中毒导致H^+/K^+ ATP酶从弥漫性分布向顶端定位转移，提示H^+/K^+ ATP酶可能参与了酸碱平衡的调节。H^+/K^+ ATP酶在慢性代谢性脂肪肝中呈弱阳性反应。少

We performed this research to elucidate the function of the main excretory duct of the submandibular gland of the rat (9-week-old male Wistar rat). Following results were obtained during 2003-2005.1.The localization of G α gustducin and G α O, the GTP-binding protein a subunits implicated in taste signal transduction and ion channel were investigated in the main excretory duct epithelium of the rat submandibular gland using immunocytochemistry (light microscopy and electron microscopy), RT-PCR and in situ hybridization.G α gustducin immunoreactivity was observed in the tuft cell and light cell type II under electron microscopy. In the tuft cell, immuno-gold particles were present on the microvilli and near the apical vesicles. In light cell type II, luminal surface and vesicles just beneath the lumen were reacted with immuno-gold particles. RT-PCR of total RNA extracted from the MED showed positive bands corresponding to the mature (spliced) α gustducin mRNA. Signal was present in spin … More dle-shaped cells (tuft cells) and cells with a bulging apex (light cells type II) with in situ,hybridization using DIG-labeled antisense ribonucleotide probesG α O immunoreactivity was observed in the all cell types without the basal cell composing the main excretory duct. Especially, tuft cells and light cells type II had the strong immunoreactivity. As well as G α gustducin immunoreactivity, immuno-gold particles were present on the microvilli and near the apical vesicles in the tuft cells, and luminal surface and vesicles just beneath the lumen in the light cells type II. RT-PCR of total RNA extracted from the MED showed positive bands corresponding to the mature (spliced) α O mRNA. Signal was present in all cell types without basal cells with in situ hybridization using DIG-labeled antisense ribonucleotide probes.2.We examined the change of H^+/K^+ATPase in chronic acidosis and chronic alkalosis by immunocytochemistry (light microscopy and electron microscopy). H^+/K^+ATPase immunoreactivity was distributed intracellularly in control. Chronic metabolic acidosis caused a shift in H^+/K^+ATPase away from diffuse distribution towards apical localization, suggesting that H^+/K^+ATPase might be involved in the regulation of acidbase homeostasis. The week immunoreactivity with H^+/K^+ATPase was present in Chronic metabolic alkalosis. Less