Hume R, Coughtrie M W, Burchell B
Department of Obstetrics and Gynaecology, University of Dundee Medical School, Ninewells Hospital, UK.
Arch Toxicol. 1995;69(4):242-7. doi: 10.1007/s002040050165.
The aim of our study was to localise UDP-glucuronosyltransferase (UDPGT) in the developing mesonephric and metanephric kidneys of the human embryo and fetus, using immunohistochemical methods and an antibody preparation with broad specificity to the human isoforms. In embryonic and early fetal development of the metanephric kidney, UDPGT is located primarily in derivatives of the ureteric bud such as the ureter, pelvis, calyces and collecting ducts. This early predominance of UDPGT to ureteric bud derivatives declines by mid-fetal life: a) as nephrons evolve and develop they become increasingly UDPGT immunoreactive such that in mature metanephric kidney, the proximal tubules are highly UDPGT reactive, with other elements of the nephron also immunopositive (albeit at lower reactivities) and b) with the formation of an immunonegative transitional epithelium in ureter, pelvis and calyces, the reactivity retained in collecting ducts is only a small proportion of the total. The distribution of UDPGT immunoreactivity is relatively uniform in proximal tubular cells throughout development. This is in contrast to collecting ducts where, in fetal life, this reactivity is displaced to apices and bases by intracellular glycogen deposits. Parietal cells of Bowman's capsule are immunoreactive, but glomeruli are negative. In mesonephric kidney, as early as 32 days post-ovulation, tubules and the mesonephric duct are UDPGT immunoreactive and mesonephric immunopositivity overlaps with that in the developing metanephric kidney.
我们研究的目的是利用免疫组织化学方法以及对人类同工型具有广泛特异性的抗体制剂，在人类胚胎和胎儿发育中的中肾和后肾中定位尿苷二磷酸葡萄糖醛酸基转移酶（UDPGT）。在胚胎期和胎儿早期后肾发育过程中，UDPGT主要位于输尿管芽的衍生物中，如输尿管、肾盂、肾盏和集合管。在胎儿中期，UDPGT在输尿管芽衍生物中的这种早期优势逐渐下降：a）随着肾单位的演化和发育，它们对UDPGT的免疫反应性越来越强，以至于在成熟的后肾中，近端小管对UDPGT反应性很高，肾单位的其他成分也呈免疫阳性（尽管反应性较低）；b）随着输尿管、肾盂和肾盏中形成免疫阴性的移行上皮，集合管中保留的反应性仅占总量的一小部分。在整个发育过程中，UDPGT免疫反应性在近端小管细胞中的分布相对均匀。这与集合管形成对比，在胎儿期，由于细胞内糖原沉积，这种反应性被转移到顶端和基部。鲍曼囊的壁层细胞呈免疫反应性，但肾小球呈阴性。在中肾中，早在排卵后32天，肾小管和中肾管就呈UDPGT免疫反应性，中肾的免疫阳性与发育中的后肾的免疫阳性重叠。
