Structure of the Bufo arenarum kidney: Renal corpuscle, neck segment and proximal tubule

Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Argentina.
Biocell: official journal of the Sociedades Latinoamericanas de Microscopía Electronica ... et. al (Impact Factor: 0.57). 01/1999; 22(3):187-96.
Source: PubMed


The structural organization of the renal corpuscle (RC), ciliated neck segment (NS) and the proximal tubule (PT) were studied in the toad, Bufo arenarum, by means of light and transmission electron microscopy. The ciliated neck segment and the proximal tubule are located in the dorsolateral zone of the kidney, while the distal tubules are located in a ventromedial zone. RC are found between these two zones. The glomerular filter apparatus consists of the podocyte epithelium, a basement membrane, a subendothelial space and an endothelium. The podocyte emits cytoplasmatic processes extending over the surface of the glomerular capillaries. These processes divide into further processes ending in expansions known as pediceles. The basement membrane consists of a lamina rara externa and a rather thin lamina densa, while the subendothelial space contains collagen fibers and slender cytoplasmic processes of the mesangial cells. NS are composed of ciliated cells with a characteristic location of the mitochondria. The PT consists of prismatic cells with a dense luminal brush border of long microvilli and numerous apical vesicles. The basal cell membrane is increased by small infoldings. One characteristic structure of the cytoplasm is the presence of lipid droplets. The cytological structure of PT cells can be considered as an adaptation for the reabsorption of organic materials.

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    • "In a previous study we described the organization of the kidney of B. arenarum, in particular the structure of the renal corpuscle, neck segment and proximal tubule (Farías et al., 1998). The aim of this work is to give a more detailed information on the structure of the IS, the EDT, the LDT and the CT of this species, which is frequently used as an experimental model for physiological and biochemical studies. "
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