STRUCTURE, FUNCTION AND DEVELOPMENT OF THE JUXTAGLOMERULAR APPARATUS

它们之间的结构和功能的相互关系 致密黄斑、肾小球系膜外和肾小球系膜外的其他细胞。 对肾小球旁结构(JGA)的认识还不完全。 此外，关于这一地区的发展的研究还很少。 已经进行了肾移植。我们打算使用一种组合 生理、形态和免疫细胞化学 在细胞水平上描述结构和 JGA在体内和体外的作用。首先，使用孤立的 粗大的升肢与肾小球相连，我们将检查 在体外和在组织内固定的电子显微镜结构 细胞内室和胞外室内的重排 这可能发生在管腔渗透压变化期间。第二, 血管内皮细胞外基质的通透性 JGA将在体外进行测试，添加大小的荧光粉 以及用于光学和电子显微镜的示踪剂添加到 沐浴液。第三，我们打算在体内标记 新生大鼠JGA发育过程中的细胞外基质及 研究其组装序列和细胞来源。在……里面 此外，含有肾素和血管紧张素的外观 细胞将通过免疫细胞化学方法确定并相互关联 随着肾小球发育的阶段。第四， 收购JGA的功能属性将是 通过测量发育中的血浆肾素水平来确定 动物和肾素从离断的粗大升肢释放 随附JGA制剂。最终，这些实验 在正常动物中的作用将扩展到遗传和实验 建立高血压模型以确定JGA功能障碍 和/或异常的JGA发育可能是相关的 高血压病的发病因素。

The structural and functional interrelationships between the macula densa, extraglomerular mesangium, and other cells of the juxtaglomerular apparatus (JGA) are incompletely understood. In addition, few studies on the development of this area of the nephron have been undertaken. We intend to use a combination of physiological, morphological, and immunocytochemical techniques to describe, at a cellular level, the structure and function of the JGA in vivo and in vitro. First, using the isolated thick ascending limb with attached glomerulus, we will examine in vitro and in tissue fixed for electron microscopy structural rearrangements within intra- and extracellular compartments that might occur during changes in luminal osmolality. Second, the permeability properties of the extracellular matrix of the JGA will be tested in vitro with the addition of sized fluorphores and tracers for light and electron microscopy added to the bathing solution. Third, we intend to label in vivo the extracellular matrix of the developing JGA of newborn rats and rabbits to study its sequence of assembly and cellular origin. In addition, the appearance of renin- and angiotensin-containing cells will be determined immunocytochemically and correlated with the stage of glomerular development. Fourth, the acquisition of functional properties of the JGA will be determined by measuring plasma renin levels in developing animals and renin release from the isolated thick ascending limb with attached JGA preparation. Ultimately, these experiments in normal animals will be extended to genetic and experimental models of hypertension to determine whether JGA dysfunction and/or abnormal JGA development might be one of the relevant factors contributing to the development of hypertension.