WATER AND ELECTROLYTES IN HEALTH AND DISEASE

水和电解质与健康和疾病的关系

基本信息

批准号：
3151114
负责人：
FRANKLIN H EPSTEIN
金额：
$ 26.18万
依托单位：
BETH ISRAEL DEACONESS MEDICAL CENTER
依托单位国家：
美国
项目类别：
财政年份：
1974
资助国家：
美国
起止时间：
1974-09-01 至 1987-11-30
项目状态：
已结题

项目摘要

The role of reduced glutathione in preserving renal function and structure will be investigated, using the isolated perfused rat kidney as a model. We have preliminary evidence that glutathione depletion may produce lesions localized to the thick ascending limb associated with disproportionate reduction in concentrating ability. Specific inhibition of GSH synthesis and cellular depletion of GSH in a variety of ways will be employed, and an attempt made to correlate histological evidence of structural damage to cells and functional alterations, with tissue levels of reduced thiols, using both histochemical and enzymatic methods to evaluate this. The way in which Na-K-ATPase is activated when transepithelial transport is increased will be studied in the isolated perfused elasmobranch rectal gland. Intracellular sodium will be monitored non-invasively and sequentially by a new technique using nuclear magnetic resonance (23Na NMR). Steady-state levels of phosphorus intermediates will also be estimated with 31P NMR, together with the unidirectional rates of phosphate turnover, using the method of saturation transfer. Changes in intracellular electrical potential will be evaluated in separated tubules and cells before and after stimulation of transport, using fluorescent and radioactive probes. Alterations in ouabain binding of rectal gland cells will be assessed before and after secretion is stimulated. The possibility of interchange of pump enzyme between cell interior and plasma membranes by the mechanisms of exocytosis and of membrane internalization will be investigated. The possible role of protein kinase in activating cell membrane Na-K-ATPase will also be explored in direct experiments using partially purified enzyme and protein kinase prepared from rectal gland tissue.

还原型谷胱甘肽在保护肾功能和结构中的作用将使用分离的灌注大鼠肾脏作为模型进行研究。我们有初步证据表明谷胱甘肽消耗可能会产生病变局限于与不成比例相关的粗升肢注意力集中能力下降。特异性抑制 GSH 合成将采用多种方式去除细胞中的 GSH，并且尝试将结构损伤的组织学证据与细胞和功能改变，组织中硫醇水平降低，使用组织化学和酶法来评估这一点。道路当跨上皮运输发生时，Na-K-ATP酶被激活将在离体灌注软骨鱼直肠中研究增加的腺。将无创地监测细胞内的钠依次通过使用核磁共振的新技术（23Na 核磁共振）。磷中间体的稳态水平也将用 31P NMR 以及磷酸盐的单向速率估计周转，采用饱和转移的方法。变化将在分离的小管中评估细胞内电位以及运输刺激之前和之后的细胞，使用荧光和放射性探针。直肠腺细胞哇巴因结合的改变将在刺激分泌之前和之后进行评估。可能性细胞内部和质膜之间泵酶的交换胞吐作用和膜内化的机制将是调查了。蛋白激酶在激活细胞中的可能作用膜 Na-K-ATP 酶也将在直接实验中进行探索从直肠腺制备的部分纯化的酶和蛋白激酶组织。