STRUCTURE, FUNCTION AND DEVELOPMENT OF THE JUXTAGLOMERULAR APPARATUS

结构和功能之间的相互关系 致密斑、肾小球外系膜和肾小球的其他细胞。 肾小球器（JGA）的认识不完全。 此外，关于这一领域发展的研究很少， 肾单位已进行。 我们打算用一种组合 生理形态和免疫细胞化学 技术来描述，在细胞水平上，结构和 JGA在体内和体外的功能。 首先，使用隔离的 厚的升支与肾小球相连，我们将检查 在体外和组织中固定用于电子显微镜结构 细胞内和细胞外区室的重排 这可能发生在管腔渗透压变化期间。 第二、 的细胞外基质的渗透性特性， JGA将在体外进行测试，并添加大小的荧光团 和示踪剂的光学和电子显微镜添加到 沐浴液 第三，我们打算在体内标记 新生大鼠发育中JGA的细胞外基质， 兔研究其组装序列和细胞起源。 在 此外，含肾素和血管紧张素的血管紧张素的出现， 将通过免疫细胞化学方法测定细胞， 肾小球发育的阶段。 四是 JGA功能特性的获取将 通过测量发展中国家的血浆肾素水平来确定 动物和肾素释放从孤立的厚升支 并附有JGA准备。 最终，这些实验 将扩展到遗传和实验 高血压模型，以确定是否JGA功能障碍 和/或异常的JGA发展可能是相关的 导致高血压发展的因素。

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.