Related Experiment Video
Updated: Mar 13, 2026

Culturing Primary Rat Inner Medullary Collecting Duct Cells
Published on: June 21, 2013
Molecular mechanisms regulating aquaporin-2 in kidney collecting duct
Hyun Jun Jung1, Tae-Hwan Kwon2
1Epithelial Systems Biology Laboratory, Systems Biology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland; and.
Abstract:
The kidney collecting duct is an important renal tubular segment for regulation of body water homeostasis and urine concentration. Water reabsorption in the collecting duct principal cells is controlled by vasopressin, a peptide hormone that induces the osmotic water transport across the collecting duct epithelia through regulation of water channel proteins aquaporin-2 (AQP2) and aquaporin-3 (AQP3). In particular, vasopressin induces both intracellular translocation of AQP2-bearing vesicles to the apical plasma membrane and transcription of the Aqp2 gene to increase AQP2 protein abundance. The signaling pathways, including AQP2 phosphorylation, RhoA phosphorylation, intracellular calcium mobilization, and actin depolymerization, play a key role in the translocation of AQP2. This review summarizes recent data demonstrating the regulation of AQP2 as the underlying molecular mechanism for the homeostasis of water balance in the body.
Related Concept Videos
Aquaporins
Reabsorption and Secretion in the DCT and Collecting Duct
The distal...
Physiology of the Genitourinary System II: Tubular Reabsorption and Secretion
Renal Tubule and Collecting Duct
Proximal Convoluted Tubule (PCT):
The PCT is the initial segment of the renal tubule, extending from the Bowman's capsule that encloses the glomerulus. Its convoluted structure and microvilli-lined cells increase the surface area for reabsorption. The PCT reabsorbs glucose, amino acids, sodium, and water from the filtrate, ensuring essential...
Endocrine Signaling
Physiology of the Genitourinary System III: Urine Concentration and Dilution

