What do aquaporins do?
Aquaporins are membrane channels expressed in almost every organism and involved in the bidirectional transfer of water and small solutes across cell membranes.
What is the role of aquaporin 2?
The aquaporin 2 water channel plays an essential role in maintaining the body’s water balance. The placement of these channels is controlled by a hormone called vasopressin or antidiuretic hormone (ADH).
Where is aquaporin 2 found?
kidney
Aquaporin-2 (AQP-2) is found in the apical cell membranes of the kidney’s collecting duct principal cells and in intracellular vesicles located throughout the cell. It is encoded by the AQP2 gene.
What happens if aquaporin stops working?
When plant aquaporins are silenced, the hydraulic conductance and photosynthesis of the leaf decrease. When gating of plant aquaporins occurs, it stops the flow of water through the pore of the protein.
Can water pass through cell membrane without aquaporins?
Cell-membrane water permeability varies considerably from cell to cell; high permeability denotes a fluid lipid bilayer and expression of AQPs. Low water permeability occurs when there is no aquaporin expression and membrane is rich in cholesterol.
What role does AQP2 play in Osmoregulation?
AQP2 water channels mediate osmotic water transport across the apical membranes of principal cells in the renal collecting duct. These water channels are regulated in response to binding of vasopressin to V2 receptors in the basolateral plasma membrane.
What is the treatment for nephrogenic diabetes insipidus?
Nephrogenic diabetes insipidus. Treatment with the drug hydrochlorothiazide (Microzide) may improve your symptoms. Although hydrochlorothiazide is a type of drug that usually increases urine output (diuretic), it can reduce urine output for some people with nephrogenic diabetes insipidus.
Does collecting duct have aquaporins?
Out of at least 10 aquaporin isoforms, at least 7 are known to be present in the kidney at distinct sites along the nephron and collecting duct. Aquaporin-1 (AQP1) is extremely abundant in the proximal tubule and descending thin limb where it appears to be the main site for proximal nephron water reabsorption.
How many aquaporins are in the human body?
13 mammalian aquaporins
There are 13 mammalian aquaporins, which are widely distributed in specific cell types in many organs and tissues. Their primary function is to facilitate water transport across cell plasma membranes; some AQPs (called aquaglyceroporins) also transport glycerol.
Where are aquaporins found in humans?
AQP4 is present in the brain astrocytes, eye, ear, skeletal muscle, stomach parietal cells, and kidney collecting ducts. AQP5 is in the secretory cells such as salivary, lacrimal, and sweat glands. AQP5 is also expressed in the ear and eye. AQP6 is localized intracellular vesicles in the kidney collecting duct cells.