• Citer

The renal connecting tubule: Resolved and unresolved issues in Ca(2+) transport.

par Markadieu, Nicolas ;Bindels, René R.J.;Hoenderop, Joost J.G.
Référence International journal of biochemistry & cell biology, 43, 1, page (1-4)
Publication Publié, 2011-01

Article révisé par les pairs

• Accès en ligne
• Détails
• Contenu
• Statistiques

Résumé :

The renal connecting tubule (CNT) localizes to the distal part of the nephron between the distal convoluted tubule and the collecting duct, and consists of two different cell types: segment-specific and intercalated cells. The former reabsorb water (H(2)O), sodium (Na(+)) and calcium (Ca(2+)) ions to the blood compartment, while secreting potassium ions (K(+)) into the pro-urine. The latter cells contribute to the renal control of the acid-base balance. Several factors and hormones tightly regulate these transport processes. Although the CNT reabsorbs only ∼15% of filtered Ca(2+) load, this segment is finally decisive for the amount of Ca(2+) that appears in the urine. Impaired Ca(2+) transport across CNT can provoke severe urinary Ca(2+) excretion, called hypercalciuria. This review mainly focuses on the activity, abundance and expression of the epithelial Ca(2+) channel named Transient Receptor Potential Vanilloid 5 (TRPV5) that is the gatekeeper of active Ca(2+) reabsorption in the CNT.