Bidman H J, Radu I, Stumpf W E
Department of Neuroanatomy, Heinrich-Heine-University, Düsseldorf, Germany.
Rom J Morphol Embryol. 1997 Jul-Dec;43(3-4):91-101.
The distribution of specific binding sites for vitamin D3 in adult female and male Xiphophorus helleri is studies after injection of tritiated 1,25-dihydroxyvitamin D3 (vitamin D) by thaw-mount autoradiography. Five hours after injection of labeled vitamin D specific nuclear binding is present in brain, pituitary, skin, gills, cartilage, gut, liver, pancreas, spleen, kidney, muscle, ovary, and testis. Cytoplasmic binding exists strongest in gills, gut, and kidney while it is comparatively weak in hepatocytes. In reproductive organs cytoplasmic retention of radioactivity is also present in oocytes. Weak nuclear labeling exists in interstitial cells in ovary. Conspicuous nuclear labeling exists in active lobules of testis, while inactive lobules show occasionally a few labeled cells. The results demonstrate specific binding and retention of vitamin D in many target organs of teleost fish, suggesting an extensive and multifunctional regulatory role of this steroid hormone of sunlight.
通过冻融切片放射自显影术，研究了成年雌性和雄性剑尾鱼中维生素D3特异性结合位点的分布情况，实验在注射氚标记的1,25 - 二羟基维生素D3（维生素D）后进行。注射标记维生素D五小时后，在脑、垂体、皮肤、鳃、软骨、肠道、肝脏、胰腺、脾脏、肾脏、肌肉、卵巢和睾丸中均出现特异性核结合。细胞质结合在鳃、肠道和肾脏中最强，而在肝细胞中相对较弱。在生殖器官中，卵母细胞中也存在放射性的细胞质保留。卵巢间质细胞中存在微弱的核标记。睾丸的活跃小叶中存在明显的核标记，而不活跃小叶偶尔可见少量标记细胞。结果表明硬骨鱼的许多靶器官中存在维生素D的特异性结合和保留，提示这种阳光类固醇激素具有广泛且多功能的调节作用。
