Organ
Distal convoluted tubule
A cortical segment for controlled electrolyte recovery
High-yield
The apical NaCl cotransporter NCC is the thiazide target. Regulated calcium transport is especially important in the later distal tubule and connecting region, where parathyroid hormone promotes calcium recovery.
Overview
After the thick ascending limb, tubular fluid enters a short convoluted segment with mitochondria-rich cuboidal cells and little apical microvillus development. The distal convoluted tubule adjusts sodium chloride, magnesium and calcium recovery before fluid reaches the connecting tubule.
Reference facts
- Location
- Located in the cortical labyrinth downstream of the macula-densa-containing terminal thick ascending limb.
- Parts
- Early and late DCT regions lead into the connecting tubule; cuboidal cells lack the dense proximal brush border.
- Blood supply
- Cortical peritubular capillaries receive reabsorbed substances and support epithelial metabolism.
- Innervation
- Renal sympathetic pathways influence transport alongside local and hormonal regulatory mechanisms.
- Function
- Reabsorbs sodium chloride with low water permeability and fine-tunes magnesium and calcium excretion.
Clinical correlation
Loss of NCC function causes Gitelman syndrome, typically with salt wasting, hypokalemic alkalosis, low magnesium and reduced urinary calcium. Thiazides affect the same transporter and can cause hyponatremia; reduced urinary calcium does not by itself establish a treatment's benefit for recurrent stones.
Frequently asked questions
Where is the distal convoluted tubule located?
The distal convoluted tubule lies located in the cortical labyrinth downstream of the macula-densa-containing terminal thick ascending limb.
What does the distal convoluted tubule do?
Reabsorbs sodium chloride with low water permeability and fine-tunes magnesium and calcium excretion.
What are the parts of the distal convoluted tubule?
Early and late DCT regions lead into the connecting tubule; cuboidal cells lack the dense proximal brush border.
What is the blood supply of the distal convoluted tubule?
The distal convoluted tubule is supplied by the cortical peritubular capillaries receive reabsorbed substances and support epithelial metabolism.