BACKGROUND Aquaporin (AQP) 3 and AQP 5 are involved in tumorigenesis and tumor progression of several tumor types. AIM To investigate expression patterns and clinical significance of AQP3 and AQP5 in hepatocellular carcinoma (HCC). METHODS Immunohistochemistry was performed to detect the expression of AQP3 and AQP5 in HCC tissues. RESULTS Immunohistochemistry analysis showed the increased...

The aquaporins (AQP) are water channel proteins playing a major role in transcellular and transepithelial water movement. Recently, the role of AQPs in human carcinogenesis has become an area of great interest. Here, by immunohistochemistry (IHC), we have found an expression of AQP5 protein in 35.3% (IHC-score: > or = 1, 144/408) of the resected NSCLC tissue samples. Cases with AQP5-positive st...

PURPOSE Aquaporins (AQPs) play a significant role in the movement of water across the plasma membrane. In the eye, the cornea and lens are avascular with unique microcirculatory mechanisms to meet the metabolic demands. We have previously shown that AQP0 and AQP1 water channels participate in maintaining lens transparency and homeostasis. In the present investigation, we explored the expression...

Aquaporins (AQPs) are channel proteins that regulate the movement of water through the plasma membrane of secretory and absorptive cells in response to osmotic gradients. In the salivary gland, AQP5 is the major aquaporin expressed on the apical membrane of acinar cells. Previous studies have shown that the volume of saliva secreted by AQP5-deficient mice is decreased, indicating a role for AQP...

Aquaporin membrane protein channels mediate cellular water flow. Human aquaporin 5 (AQP5) is highly expressed in the respiratory system and secretory glands where it facilitates the osmotically-driven generation of pulmonary secretions, saliva, sweat and tears. Dysfunctional trafficking of AQP5 has been implicated in several human disease states, including Sjögren's syndrome, bronchitis and cys...

Aquaporin-5 (AQP5) is a water-specific channel located on the apical surface of airway epithelial cells. In addition to regulating transcellular water permeability, AQP5 can regulate paracellular permeability, though the mechanisms by which this occurs have not been determined. Microtubules also regulate paracellular permeability. Here, we report that AQP5 promotes microtubule assembly and help...

Aquaporin-5 (AQP5) is a water channel protein expressed on the apical surface of alveolar epithelial type I cells in distal rat lung, suggesting a role for AQP5 in regulating alveolar surface liquid tonicity and/or cell volume. We investigated the molecular mechanisms underlying hypertonic induction of AQP5 in primary rat alveolar epithelial cells (AEC). Steady-state levels of AQP5 mRNA and pro...

The present study investigated the role of nitric oxide (NO)/cGMP signal transduction in the M(3) muscarinic acetylcholine receptor (mAChR)-stimulated increase in aquaporin-5 (AQP5) levels in the apical plasma membrane (APM) of rat parotid glands. Pretreatment of rat parotid tissue with the NO scavenger 2-(4carboxyphenyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide potassium inhibited both a...

Chronic obstructive pulmonary disease (COPD) causes significant morbidity and mortality. Cigarette smoke, the most common risk factor for COPD, induces airway and alveolar epithelial barrier permeability and initiates an innate immune response. Changes in abundance of aquaporin 5 (AQP5), a water channel, can affect epithelial permeability and immune response after cigarette smoke exposure. To d...

BACKGROUND We recently reported that aquaporin 5 (AQP5), a water channel never identified in the kidney before, co-localizes with pendrin at the apical membrane of type-B intercalated cells in the kidney cortex. Since co-expression of AQP5 and pendrin in the apical membrane domain is a common feature of several other epithelia such as cochlear and bronchial epithelial cells, we evaluated here w...