Different patterns of agonist-induced modulation of α1B-adrenoceptor density at different initial expression levels

We compared the norepinephrine (NE) induced α_1B-adrenoceptor (α_1B-AR) expression modulation between two transfected human embryonic kidney (MEK) 293 cell lines in which α_1B-AR densities were (6 336 ± 913) and (773 ± 164) fmol ▪ mg¹, respectively. Treatment of cells with NE (10 μmol ▪ L₁) for 48 h decreased high-level expressed α_1B-AR density, but increased low-level expressed α_1B-AR density. The protein kinase C inhibitor Calphostin C or Ro-31-8220 reversed, and its activator PMA mimicked the NE-induced down-regulation of high-level expressed α_1B-AR. Moreover, PMA induced a down-regulation of low-level expressed α_1B-AR. The endoplasmic reticulum Ca²⁺-ATPase inhibitor cyclopiazonic acid (CPA) and the calcium chelator BAPTA/AM did not affect the down-regulation of high-level expressed α_1B-AR, but inhibited the up-regulation of low-level expression α_1B-AR induced by NE. These results suggest that α_1B-adrenoceptor densities at different initial expression levels are differentially regulated by NE and their signal transduction pathways are different.     

Effect of latent iron deficiency on the levels of iron,calcium, zinc,copper, manganese,cadmium and lead in liver,kidney and spleen of growing rats

Summary Feeding a marginally low iron content diet (18–20 mg iron/kg diet) to weaned (21-day-old) rats for 8 weeks produced a significant decrease in liver non-heme iron (66%, p<0.001) but no change in blood hemoglobin. Total iron contents of liver (56%, p<0.01), spleen (20%, p<0.05), and kidney (19%, p<0.05) were also found to decrease along with increased zinc, copper, calcium, manganese lead and cadmium in various organs. The magnitude of alteration of a metal was different in different organs. However, liver was found to be the most affected organ. Two weeks of rehabilitation with iron-sufficient diet (390 mg iron/kg diet) normalized these altered levels.     

采用ICP-AES法测定香烟烟气成分中金属离子在动物体内的蓄积

通过动物被动吸烟模型,考察大白兔在被动吸烟后不同时期肾脏组织样本中7种重金属(Hg,Se,Sn,Pb,Pd,Ni和Cr)含量的变化,用微波酸湿消化法处理试样制备测试液,用电感耦合等离子体原子发射光谱法(ICP-AES法)同时测定Hg,Se,Sn,Pb,Pd,Ni和Cr这7种元素的含量.研究结果表明:采用ICP-AES法,加标回收率达95.0％～104.2％,相对标准偏差为1.3％～4.1％,具有良好的准确度和精密度;大白兔在被动吸食香烟后肾脏中Hg,Se,Pb,Cd和Cr这5种金属离子含量显著提高,并以吸食NISE组香烟金属离子含量提高最大,经12周后,以上几种元素在肾脏中含量较正常组分别高5.6,8.1,12.9,4.7和3.8倍.     

黔江肾豆营养成分分析

该研究测定了重庆黔江肾豆的主要营养成分及矿物质元素质量分数.研究发现黔江肾豆粗蛋白质量分数为23.35%,蛋白质质量分数为14.28%,水解液总氨基酸质量分数为17.0%,总必需氨基酸质量分数为6.9%;粗脂肪质量分数为1.28%,不饱和脂肪酸质量分数较高,占总脂肪酸的83.0%,其中油酸为8.2%,亚油酸为22.2%,α-亚麻酸的质量分数均超过大豆、黑豆、豇豆和鹰嘴豆等豆科作物,占总脂肪酸质量分数的52.6%;总糖质量分数为53.47%,其中还原糖为1.70%,淀粉为51.77%;粗纤维为3.47%;主要矿质元素,铁:68.2μg/g,锌:42.9μg/g,钙:10.3μg/g,钾:7.3mg/g,镁:1.8mg/g,锰:16.5μg/g,铜:9.4μg/g,磷:2.62mg/g.可见黔江肾豆营养保健价值独特(特别富含α-亚麻酸),值得开发利用.     

Molecular basis of autosomal-dominant polycystic kidney disease

Autosomal-dominant polycystic kidney disease (ADPKD) is one of the most common monogenetic diseases in humans. The discovery that mutations in the PKD1 and PKD2 genes are responsible for ADPKD has sparked extensive research efforts into the physiological and pathogenetic role of polycystin-1 and polycystin-2, the proteins encoded by these two genes. While polycystin-1 may mediate the contact among cells or between cells and the extracellular matrix, a lot of evidence suggests that polycystin-2 represents an endoplasmic reticulum-bound cation channel. Cyst development has been compared to the growth of benign tumors and this view is highlighted by the model that a somatic mutation in addition to the germline mutation is responsible for cystogenesis (two-hit model of cyst formation). Since in vitro polycystin-1 and polycystin-2 interact through their COOH termini, the two proteins possibly act in a common pathway, which controls the width of renal tubules. The loss of one protein may lead to a disruption of this pathway and to the uncontrolled expansion of tubules. Our increasing knowledge of the molecular events in ADPKD has also started to be useful in designing novel diagnostic and therapeutic strategies. Received 12 September 2001; received after revision 7 November 2001; accepted 7 November 2001     

原位低温下肾血流阻断肾实质切开治疗铸形结石23例

采用原位低温下肾血流阻断无萎缩无积水肾盂联合肾实质切开取石术治疗23例肾铸形结石,结果表明:20例全部取净结石,3例有残石;23例术后3个月IVP检查肾显影良好,血肌酐检查正常.本术式具有出血少,手术视野清晰,取石较彻底,对肾功能无损害的优点.     

西藏毛腿沙鸡泌尿系统解剖

对l例雌性西藏毛腿沙鸡泌尿系统进行了形态学观察。结果表明：雌性西藏毛腿沙鸡泌尿系统与大多数鸟类一样，只有一对肾脏和一对输尿管。     

15-Hydroxyprostaglandin dehydrogenase and hexokinase in spontaneously hypertensive rat kidney

Summary 15-Hydroxyprostaglandin dehydrogenase (PGDH) surged in hypertensive (SHR) and normotensive (WKY) rat kidney at 8 days of age, is greatest in SHR. Hexokinase fell in SHR at 17 days of age, but thereafter was similar to WKY. This suggests multisystem enzymatic abnormalities in SHR kidney during development of hypertension.