Arai R, Jacobowitz D M, Hida T
Department of Anatomy, Fujita Health University School of Medicine, Toyoake, Aichi, Japan.
Cell Tissue Res. 1999 Oct;298(1):11-9.
The aim of the present study was to examine quantitatively whether two calcium-binding proteins, calbindin D28k and calretinin, are localized in oxytocin and vasopressin neurons of the supraoptic nucleus of the male rat. We used a triple-labeling immunofluorescence method with a confocal laser scanning microscope. Of the oxytocin-labeled cells, 70% were stained for both calbindin D28k and calretinin, 15% were stained for only calbindin D28k, 13% were stained for only calretinin, and 2% were stained for neither protein. Of the vasopressin-labeled cells, 73% were stained for neither calbindin D28k nor calretinin, 21% were stained for only calbindin D28k, 4% were stained for only calretinin, and 2% were stained for both proteins. Calbindin D28k and calretinin have been shown previously to contribute to calcium homeostasis by buffering [Ca2+]i. Therefore, these findings suggest that most of the oxytocin neurons may have a higher Ca(2+)-buffering capacity than most of the vasopressin neurons.
本研究的目的是定量检测两种钙结合蛋白，即钙结合蛋白D28k和钙视网膜蛋白，是否定位于雄性大鼠视上核的催产素和加压素神经元中。我们使用共聚焦激光扫描显微镜的三重标记免疫荧光法。在催产素标记的细胞中，70%的细胞同时被钙结合蛋白D28k和钙视网膜蛋白染色，15%的细胞仅被钙结合蛋白D28k染色，13%的细胞仅被钙视网膜蛋白染色，2%的细胞两种蛋白均未被染色。在加压素标记的细胞中，73%的细胞既未被钙结合蛋白D28k也未被钙视网膜蛋白染色，21%的细胞仅被钙结合蛋白D28k染色，4%的细胞仅被钙视网膜蛋白染色，2%的细胞两种蛋白均被染色。先前已表明钙结合蛋白D28k和钙视网膜蛋白通过缓冲[Ca2+]i来维持钙稳态。因此，这些发现表明，大多数催产素神经元可能比大多数加压素神经元具有更高的Ca(2+)缓冲能力。
