How are the proximal and distal convoluted tubules different histologically?
The proximal convoluted tubule (PCT) has a brush border of microvilli, which increases the surface area for reabsorption of water, ions, and nutrients. These cells are cuboidal with large, eosinophilic cytoplasm due to abundant mitochondria.
In contrast, the distal convoluted tubule (DCT) has fewer microvilli and a clearer cytoplasm. The DCT cells are involved in the selective reabsorption and secretion of ions, contributing to the fine-tuning of electrolyte balance.
