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Aquaporins: relevance to cerebrospinal fluid physiology and therapeutic potential in hydrocephalus. Cerebrospinal Fluid Res 7:15

Kids Neurosurgical Research Unit, Institute of Neuroscience and Muscle Research, Kids Research Institute, Children's Hospital at Westmead, Hawkesbury Rd, Westmead NSW 2145, Australia. .
Cerebrospinal Fluid Research (Impact Factor: 1.81). 09/2010; 7:15. DOI: 10.1186/1743-8454-7-15
Source: PubMed

ABSTRACT The discovery of a family of membrane water channel proteins called aquaporins, and the finding that aquaporin 1 was located in the choroid plexus, has prompted interest in the role of aquaporins in cerebrospinal fluid (CSF) production and consequently hydrocephalus. While the role of aquaporin 1 in choroidal CSF production has been demonstrated, the relevance of aquaporin 1 to the pathophysiology of hydrocephalus remains debated. This has been further hampered by the lack of a non-toxic specific pharmacological blocking agent for aquaporin 1. In recent times aquaporin 4, the most abundant aquaporin within the brain itself, which has also been shown to have a role in brain water physiology and relevance to brain oedema in trauma and tumours, has become an alternative focus of attention for hydrocephalus research. This review summarises current knowledge and concepts in relation to aquaporins, specifically aquaporin 1 and 4, and hydrocephalus. It also examines the relevance of aquaporins as potential therapeutic targets in hydrocephalus and other CSF circulation disorders.

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    • "Hydrocephalus is a condition characterized by impaired secretion, circulation and resorption of cerebrospinal fluid, resulting in ventricular dilatation [1] . This distortion has deleterious effects that include gliosis, inflammatory responses [2] , neurodegeneration [3] , axonal damage [1] , demyelination [4] , impaired cerebral blood flow [5] , and altered clearance of proteins [6] and toxins [7] . However, the mechanisms underlying these deficits are not fully understood [2] [8] . "
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    • "ATP-dependent ion pumps of the apical membrane expel Na + , Cl − , HCO 3 − and K + ions towards the ventricular lumen. Water transport, facilitated by aquaporins I of the apical membrane, follows the osmotic gradients generated by these pumps [14]. The NaK2Cl cotransporter of the apical membrane generates ion transport in both directions and participates in regulation of CSF secretion and composition. "
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