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{{Infobox_gene}}
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<!-- The GNF_Protein_box is automatically maintained by Protein Box Bot.  See Template:PBB_Controls to Stop updates. -->
'''AQP2''' is found in the apical cell membranes of the [[kidney]]'s [[collecting duct]] principal cells and in [[intracellular]] [[vesicle (biology)|vesicles]] located throughout the cell.
{{GNF_Protein_box
| image = 
| image_source = 
| PDB =
| Name = Aquaporin 2 (collecting duct)
| HGNCid = 634
| Symbol = AQP2
| AltSymbols =; AQP-CD; MGC34501; WCH-CD
| OMIM = 107777
| ECnumber = 
| Homologene = 20137
| MGIid = 1096865
| GeneAtlas_image1 = PBB_GE_AQP2_206672_at_tn.png
| Function = {{GNF_GO|id=GO:0005215 |text = transporter activity}} {{GNF_GO|id=GO:0015250 |text = water channel activity}}
| Component = {{GNF_GO|id=GO:0005624 |text = membrane fraction}} {{GNF_GO|id=GO:0005886 |text = plasma membrane}} {{GNF_GO|id=GO:0016021 |text = integral to membrane}} {{GNF_GO|id=GO:0016324 |text = apical plasma membrane}}
| Process = {{GNF_GO|id=GO:0006810 |text = transport}} {{GNF_GO|id=GO:0006833 |text = water transport}} {{GNF_GO|id=GO:0007588 |text = excretion}}
| Orthologs = {{GNF_Ortholog_box
    | Hs_EntrezGene = 359
    | Hs_Ensembl = ENSG00000167580
    | Hs_RefseqProtein = NP_000477
    | Hs_RefseqmRNA = NM_000486
    | Hs_GenLoc_db = 
    | Hs_GenLoc_chr = 12
    | Hs_GenLoc_start = 48630796
    | Hs_GenLoc_end = 48638926
    | Hs_Uniprot = P41181
    | Mm_EntrezGene = 11827
    | Mm_Ensembl = ENSMUSG00000023013
    | Mm_RefseqmRNA = NM_009699
    | Mm_RefseqProtein = NP_033829
    | Mm_GenLoc_db = 
    | Mm_GenLoc_chr = 15
    | Mm_GenLoc_start = 99407090
    | Mm_GenLoc_end = 99412579
    | Mm_Uniprot = Q3UQD4
  }}
}}


'''AQP2''' is found in the apical cell membranes of the [[kidney]]'s [[collecting duct]] principal cells and in [[intracellular]] [[vesicle (biology)|vesicles]] located throughout the cell.
== Regulation ==
 
==Regulation==
It is the only aquaporin regulated by [[vasopressin]].<ref name="pmid9824541">{{cite journal |author=Dibas AI, Mia AJ, Yorio T |title=Aquaporins (water channels): role in vasopressin-activated water transport |journal=Proc. Soc. Exp. Biol. Med. |volume=219 |issue=3 |pages=183–99 |year=1998 |pmid=9824541 |doi= |url=http://www.ebmonline.org/cgi/content/abstract/219/3/183}}</ref>


It is the only aquaporin regulated by [[vasopressin]].<ref name="pmid9824541">{{cite journal | vauthors = Dibas AI, Mia AJ, Yorio T | title = Aquaporins (water channels): role in vasopressin-activated water transport | journal = Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine | volume = 219 | issue = 3 | pages = 183–99 | date = December 1998 | pmid = 9824541 | doi = 10.3181/00379727-219-44332 }}</ref>
The basic job of aquaporin 2 is to reabsorb water from the urine while its being removed from the blood by the kidney.  Aquaporin 2 is in kidney epithelial cells and usually lies dormant in intracellular vesicle membranes. When it is needed, vasopressin binds to the cell surface vasopressin receptor thereby activating a signaling pathway that causes the aquaporin 2 containing vesicles to fuse with the plasma membrane, so the aquaporin 2 can be used by the cell.<ref>{{cite book | last1 = Lodish | first1 = Harvey | last2 = Berk | first2 = Arnold | last3 = Kaiser | first3 = Chris A. | last4 = Krieger | first4 = Monty | last5 = Scott | first5 = Matthew P. | last6 = Bretscher | first6 = Anthony | last7 = Ploegh | first7 = Hidde | last8 = Matsudaira | first8 = Paul | name-list-format = vanc | title = Molecular Cell Biology | date = 2008 | publisher = Freeman | location = New York | isbn = 978-0-7167-7601-7 | page = 445 | edition = 6th }}</ref>
This [[aquaporin]] is regulated in two ways by the [[peptide hormone]] [[vasopressin]]:  
This [[aquaporin]] is regulated in two ways by the [[peptide hormone]] [[vasopressin]]:  
* short-term regulation (minutes) through trafficking of AQP2 vesicles to the apical region where they fuse with the apical plasma membrane
* short-term regulation (minutes) through trafficking of AQP2 vesicles to the apical region where they fuse with the apical plasma membrane
* long-term regulation (days) through an increase in AQP2 gene expression.  
* long-term regulation (days) through an increase in AQP2 gene expression.
 
This [[aquaporin]] is also regulated by food intake. Fasting reduces expression of this aquaporin independently of vasopressin.
 
== Clinical significance ==


==Clinical significance==
Mutations in this channel are associated with [[nephrogenic diabetes insipidus]], which can be autosomal dominant or recessive. Mutations in the vasopressin receptor cause a similar X-linked phenotype.
Mutations in this channel are associated with [[nephrogenic diabetes insipidus]], which can be either autosomal dominant or recessive.  


[[Lithium]], which is often used to treat [[bipolar disorder]], can cause acquired [[diabetes insipidus]] by decreasing the expression of the AQP2 gene. This can result in debilitating increases in the rate of urine production.  
[[Lithium]], which is often used to treat [[bipolar disorder]], can cause acquired [[diabetes insipidus]] (characterized by the excretion of large volumes of dilute urine) by decreasing the expression of the AQP2 gene.


The expression of the AQP2 gene is increased during conditions associated with water retention such as [[pregnancy]] and [[congestive heart failure]].
The expression of the AQP2 gene is increased during conditions associated with water retention such as [[pregnancy]] and [[congestive heart failure]].


==See also==
== See also ==
* [[Aquaporin]]
* [[Aquaporin]]


==References==
== References ==
{{reflist|2}}
{{reflist}}


==Further reading==
== Further reading ==
{{refbegin | 2}}
{{refbegin|33em}}
{{PBB_Further_reading
* {{cite journal | vauthors = Bichet DG | title = Nephrogenic diabetes insipidus | journal = Advances in Chronic Kidney Disease | volume = 13 | issue = 2 | pages = 96–104 | date = April 2006 | pmid = 16580609 | doi = 10.1053/j.ackd.2006.01.006 | pmc = 2124392 }}
| citations =
* {{cite journal | vauthors = Bouley R, Hasler U, Lu HA, Nunes P, Brown D | title = Bypassing vasopressin receptor signaling pathways in nephrogenic diabetes insipidus | journal = Seminars in Nephrology | volume = 28 | issue = 3 | pages = 266–78 | date = May 2008 | pmid = 18519087 | pmc = 2494582 | doi = 10.1016/j.semnephrol.2008.03.010 }}
*{{cite journal | author=Bichet DG |title=Nephrogenic diabetes insipidus. |journal=Advances in chronic kidney disease |volume=13 |issue= 2 |pages= 96-104 |year= 2006 |pmid= 16580609 |doi= 10.1053/j.ackd.2006.01.006 }}
* {{cite journal | vauthors = Robben JH, Knoers NV, Deen PM | title = Cell biological aspects of the vasopressin type-2 receptor and aquaporin 2 water channel in nephrogenic diabetes insipidus | journal = American Journal of Physiology. Renal Physiology | volume = 291 | issue = 2 | pages = F257-70 | date = August 2006 | pmid = 16825342 | doi = 10.1152/ajprenal.00491.2005 }}
*{{cite journal | author=Robben JH, Knoers NV, Deen PM |title=Cell biological aspects of the vasopressin type-2 receptor and aquaporin 2 water channel in nephrogenic diabetes insipidus. |journal=Am. J. Physiol. Renal Physiol. |volume=291 |issue= 2 |pages= F257-70 |year= 2006 |pmid= 16825342 |doi= 10.1152/ajprenal.00491.2005 }}
* {{cite journal | vauthors = Sasaki S, Fushimi K, Saito H, Saito F, Uchida S, Ishibashi K, Kuwahara M, Ikeuchi T, Inui K, Nakajima K | title = Cloning, characterization, and chromosomal mapping of human aquaporin of collecting duct | journal = The Journal of Clinical Investigation | volume = 93 | issue = 3 | pages = 1250–6 | date = March 1994 | pmid = 7510718 | pmc = 294077 | doi = 10.1172/JCI117079 }}
*{{cite journal | author=Sasaki S, Fushimi K, Saito H, ''et al.'' |title=Cloning, characterization, and chromosomal mapping of human aquaporin of collecting duct. |journal=J. Clin. Invest. |volume=93 |issue= 3 |pages= 1250-6 |year= 1994 |pmid= 7510718 |doi= }}
* {{cite journal | vauthors = Deen PM, Weghuis DO, Sinke RJ, Geurts van Kessel A, Wieringa B, van Os CH | title = Assignment of the human gene for the water channel of renal collecting duct Aquaporin 2 (AQP2) to chromosome 12 region q12-->q13 | journal = Cytogenetics and Cell Genetics | volume = 66 | issue = 4 | pages = 260–2 | year = 1994 | pmid = 7512890 | doi = 10.1159/000133707 }}
*{{cite journal | author=Deen PM, Weghuis DO, Sinke RJ, ''et al.'' |title=Assignment of the human gene for the water channel of renal collecting duct Aquaporin 2 (AQP2) to chromosome 12 region q12-->q13. |journal=Cytogenet. Cell Genet. |volume=66 |issue= 4 |pages= 260-2 |year= 1994 |pmid= 7512890 |doi= }}
* {{cite journal | vauthors = Uchida S, Sasaki S, Fushimi K, Marumo F | title = Isolation of human aquaporin-CD gene | journal = The Journal of Biological Chemistry | volume = 269 | issue = 38 | pages = 23451–5 | date = September 1994 | pmid = 7522228 | doi =  }}
*{{cite journal | author=Uchida S, Sasaki S, Fushimi K, Marumo F |title=Isolation of human aquaporin-CD gene. |journal=J. Biol. Chem. |volume=269 |issue= 38 |pages= 23451-5 |year= 1994 |pmid= 7522228 |doi= }}
* {{cite journal | vauthors = van Lieburg AF, Verdijk MA, Knoers VV, van Essen AJ, Proesmans W, Mallmann R, Monnens LA, van Oost BA, van Os CH, Deen PM | title = Patients with autosomal nephrogenic diabetes insipidus homozygous for mutations in the aquaporin 2 water-channel gene | journal = American Journal of Human Genetics | volume = 55 | issue = 4 | pages = 648–52 | date = October 1994 | pmid = 7524315 | pmc = 1918308 | doi =  }}
*{{cite journal | author=van Lieburg AF, Verdijk MA, Knoers VV, ''et al.'' |title=Patients with autosomal nephrogenic diabetes insipidus homozygous for mutations in the aquaporin 2 water-channel gene. |journal=Am. J. Hum. Genet. |volume=55 |issue= 4 |pages= 648-52 |year= 1994 |pmid= 7524315 |doi=  }}
* {{cite journal | vauthors = Saito F, Sasaki S, Chepelinsky AB, Fushimi K, Marumo F, Ikeuchi T | title = Human AQP2 and MIP genes, two members of the MIP family, map within chromosome band 12q13 on the basis of two-color FISH | journal = Cytogenetics and Cell Genetics | volume = 68 | issue = 1-2 | pages = 45–8 | year = 1994 | pmid = 7525161 | doi = 10.1159/000133885 }}
*{{cite journal | author=Saito F, Sasaki S, Chepelinsky AB, ''et al.'' |title=Human AQP2 and MIP genes, two members of the MIP family, map within chromosome band 12q13 on the basis of two-color FISH. |journal=Cytogenet. Cell Genet. |volume=68 |issue= 1-2 |pages= 45-8 |year= 1994 |pmid= 7525161 |doi=  }}
* {{cite journal | vauthors = Nielsen S, Chou CL, Marples D, Christensen EI, Kishore BK, Knepper MA | title = Vasopressin increases water permeability of kidney collecting duct by inducing translocation of aquaporin-CD water channels to plasma membrane | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 92 | issue = 4 | pages = 1013–7 | date = February 1995 | pmid = 7532304 | pmc = 42627 | doi = 10.1073/pnas.92.4.1013 }}
*{{cite journal | author=Nielsen S, Chou CL, Marples D, ''et al.'' |title=Vasopressin increases water permeability of kidney collecting duct by inducing translocation of aquaporin-CD water channels to plasma membrane. |journal=Proc. Natl. Acad. Sci. U.S.A. |volume=92 |issue= 4 |pages= 1013-7 |year= 1995 |pmid= 7532304 |doi= }}
* {{cite journal | vauthors = Brown D | title = The ins and outs of aquaporin-2 trafficking | journal = American Journal of Physiology. Renal Physiology | volume = 284 | issue = 5 | pages = F893-901 | date = May 2003 | pmid = 12676734 | doi = 10.1152/ajprenal.00387.2002 }}
*{{cite journal | author=Maruyama K, Sugano S |title=Oligo-capping: a simple method to replace the cap structure of eukaryotic mRNAs with oligoribonucleotides. |journal=Gene |volume=138 |issue= 1-2 |pages= 171-4 |year= 1994 |pmid= 8125298 |doi= }}
* {{cite journal | vauthors = Maruyama K, Sugano S | title = Oligo-capping: a simple method to replace the cap structure of eukaryotic mRNAs with oligoribonucleotides | journal = Gene | volume = 138 | issue = 1-2 | pages = 171–4 | date = January 1994 | pmid = 8125298 | doi = 10.1016/0378-1119(94)90802-8 }}
*{{cite journal |author=Deen PM, Verdijk MA, Knoers NV, ''et al.'' |title=Requirement of human renal water channel aquaporin-2 for vasopressin-dependent concentration of urine. |journal=Science |volume=264 |issue= 5155 |pages= 92-5 |year= 1994 |pmid= 8140421 |doi= }}
* {{cite journal | vauthors = Deen PM, Verdijk MA, Knoers NV, Wieringa B, Monnens LA, van Os CH, van Oost BA | title = Requirement of human renal water channel aquaporin-2 for vasopressin-dependent concentration of urine | journal = Science | volume = 264 | issue = 5155 | pages = 92–5 | date = April 1994 | pmid = 8140421 | doi = 10.1126/science.8140421 }}
*{{cite journal | author=Oksche A, Möller A, Dickson J, ''et al.'' |title=Two novel mutations in the aquaporin-2 and the vasopressin V2 receptor genes in patients with congenital nephrogenic diabetes insipidus. |journal=Hum. Genet. |volume=98 |issue= 5 |pages= 587-9 |year= 1996 |pmid= 8882880 |doi= }}
* {{cite journal | vauthors = Oksche A, Möller A, Dickson J, Rosendahl W, Rascher W, Bichet DG, Rosenthal W | title = Two novel mutations in the aquaporin-2 and the vasopressin V2 receptor genes in patients with congenital nephrogenic diabetes insipidus | journal = Human Genetics | volume = 98 | issue = 5 | pages = 587–9 | date = November 1996 | pmid = 8882880 | doi = 10.1007/s004390050264 }}
*{{cite journal | author=Mulders SM, Knoers NV, Van Lieburg AF, ''et al.'' |title=New mutations in the AQP2 gene in nephrogenic diabetes insipidus resulting in functional but misrouted water channels. |journal=J. Am. Soc. Nephrol. |volume=8 |issue= 2 |pages= 242-8 |year= 1997 |pmid= 9048343 |doi= }}
* {{cite journal | vauthors = Mulders SM, Knoers NV, Van Lieburg AF, Monnens LA, Leumann E, Wühl E, Schober E, Rijss JP, Van Os CH, Deen PM | title = New mutations in the AQP2 gene in nephrogenic diabetes insipidus resulting in functional but misrouted water channels | journal = Journal of the American Society of Nephrology | volume = 8 | issue = 2 | pages = 242–8 | date = February 1997 | pmid = 9048343 | doi =  }}
*{{cite journal | author=Ma T, Yang B, Umenishi F, Verkman AS |title=Closely spaced tandem arrangement of AQP2, AQP5, and AQP6 genes in a 27-kilobase segment at chromosome locus 12q13. |journal=Genomics |volume=43 |issue= 3 |pages= 387-9 |year= 1997 |pmid= 9268644 |doi= 10.1006/geno.1997.4836 }}
* {{cite journal | vauthors = Ma T, Yang B, Umenishi F, Verkman AS | title = Closely spaced tandem arrangement of AQP2, AQP5, and AQP6 genes in a 27-kilobase segment at chromosome locus 12q13 | journal = Genomics | volume = 43 | issue = 3 | pages = 387–9 | date = August 1997 | pmid = 9268644 | doi = 10.1006/geno.1997.4836 }}
*{{cite journal | author=Canfield MC, Tamarappoo BK, Moses AM, ''et al.'' |title=Identification and characterization of aquaporin-2 water channel mutations causing nephrogenic diabetes insipidus with partial vasopressin response. |journal=Hum. Mol. Genet. |volume=6 |issue= 11 |pages= 1865-71 |year= 1998 |pmid= 9302264 |doi=  }}
* {{cite journal | vauthors = Canfield MC, Tamarappoo BK, Moses AM, Verkman AS, Holtzman EJ | title = Identification and characterization of aquaporin-2 water channel mutations causing nephrogenic diabetes insipidus with partial vasopressin response | journal = Human Molecular Genetics | volume = 6 | issue = 11 | pages = 1865–71 | date = October 1997 | pmid = 9302264 | doi = 10.1093/hmg/6.11.1865 }}
*{{cite journal | author=Suzuki Y, Yoshitomo-Nakagawa K, Maruyama K, ''et al.'' |title=Construction and characterization of a full length-enriched and a 5'-end-enriched cDNA library. |journal=Gene |volume=200 |issue= 1-2 |pages= 149-56 |year= 1997 |pmid= 9373149 |doi= }}
* {{cite journal | vauthors = Suzuki Y, Yoshitomo-Nakagawa K, Maruyama K, Suyama A, Sugano S | title = Construction and characterization of a full length-enriched and a 5'-end-enriched cDNA library | journal = Gene | volume = 200 | issue = 1-2 | pages = 149–56 | date = October 1997 | pmid = 9373149 | doi = 10.1016/S0378-1119(97)00411-3 }}
*{{cite journal | author=Vargas-Poussou R, Forestier L, Dautzenberg MD, ''et al.'' |title=Mutations in the vasopressin V2 receptor and aquaporin-2 genes in 12 families with congenital nephrogenic diabetes insipidus. |journal=J. Am. Soc. Nephrol. |volume=8 |issue= 12 |pages= 1855-62 |year= 1998 |pmid= 9402087 |doi= }}
* {{cite journal | vauthors = Vargas-Poussou R, Forestier L, Dautzenberg MD, Niaudet P, Déchaux M, Antignac C | title = Mutations in the vasopressin V2 receptor and aquaporin-2 genes in 12 families with congenital nephrogenic diabetes insipidus | journal = Journal of the American Society of Nephrology | volume = 8 | issue = 12 | pages = 1855–62 | date = December 1997 | pmid = 9402087 | doi =  }}
*{{cite journal | author=Kuwahara M |title=Aquaporin-2, a vasopressin-sensitive water channel, and nephrogenic diabetes insipidus. |journal=Intern. Med. |volume=37 |issue= 2 |pages= 215-7 |year= 1998 |pmid= 9550615 |doi= }}
* {{cite journal | vauthors = Kuwahara M | title = Aquaporin-2, a vasopressin-sensitive water channel, and nephrogenic diabetes insipidus | journal = Internal Medicine | volume = 37 | issue = 2 | pages = 215–7 | date = February 1998 | pmid = 9550615 | doi = 10.2169/internalmedicine.37.215 }}
*{{cite journal | author=Mulders SM, Bichet DG, Rijss JP, ''et al.'' |title=An aquaporin-2 water channel mutant which causes autosomal dominant nephrogenic diabetes insipidus is retained in the Golgi complex. |journal=J. Clin. Invest. |volume=102 |issue= 1 |pages= 57-66 |year= 1998 |pmid= 9649557 |doi=  }}
* {{cite journal | vauthors = Mulders SM, Bichet DG, Rijss JP, Kamsteeg EJ, Arthus MF, Lonergan M, Fujiwara M, Morgan K, Leijendekker R, van der Sluijs P, van Os CH, Deen PM | title = An aquaporin-2 water channel mutant which causes autosomal dominant nephrogenic diabetes insipidus is retained in the Golgi complex | journal = The Journal of Clinical Investigation | volume = 102 | issue = 1 | pages = 57–66 | date = July 1998 | pmid = 9649557 | pmc = 509065 | doi = 10.1172/JCI2605 }}
*{{cite journal | author=Goji K, Kuwahara M, Gu Y, ''et al.'' |title=Novel mutations in aquaporin-2 gene in female siblings with nephrogenic diabetes insipidus: evidence of disrupted water channel function. |journal=J. Clin. Endocrinol. Metab. |volume=83 |issue= 9 |pages= 3205-9 |year= 1998 |pmid= 9745427 |doi= }}
* {{cite journal | vauthors = Goji K, Kuwahara M, Gu Y, Matsuo M, Marumo F, Sasaki S | title = Novel mutations in aquaporin-2 gene in female siblings with nephrogenic diabetes insipidus: evidence of disrupted water channel function | journal = The Journal of Clinical Endocrinology and Metabolism | volume = 83 | issue = 9 | pages = 3205–9 | date = September 1998 | pmid = 9745427 | doi = 10.1210/jc.83.9.3205 }}
*{{cite journal | author=Saito T, Ishikawa S, Ito T, ''et al.'' |title=Urinary excretion of aquaporin-2 water channel differentiates psychogenic polydipsia from central diabetes insipidus. |journal=J. Clin. Endocrinol. Metab. |volume=84 |issue= 6 |pages= 2235-7 |year= 1999 |pmid= 10372737 |doi=  }}
* {{cite journal | vauthors = Saito T, Ishikawa S, Ito T, Oda H, Ando F, Higashiyama M, Nagasaka S, Hieda M, Saito T | title = Urinary excretion of aquaporin-2 water channel differentiates psychogenic polydipsia from central diabetes insipidus | journal = The Journal of Clinical Endocrinology and Metabolism | volume = 84 | issue = 6 | pages = 2235–7 | date = June 1999 | pmid = 10372737 | doi = 10.1210/jc.84.6.2235 }}
}}
{{refend}}
{{refend}}


== External links ==
* [https://www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book=gene&part=ndi  GeneReviews/NCBI/NIH/UW entry on Nephrogenic Diabetes Insipidus]
* {{MeshName|Aquaporin+2}}
* {{UCSC gene info|AQP2}}


{{Ion channels|g4}}


==External links==
* {{MeshName|Aquaporin+2}}
{{Ion channels}}
[[Category:Membrane biology]]
[[Category:Membrane biology]]
[[Category:Integral membrane proteins]]
[[Category:Integral membrane proteins]]
 
[[Category:Biology of bipolar disorder]]
[[pt:Aquaporina 2]]

Latest revision as of 18:18, 15 May 2018

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Identifiers
Aliases
External IDsGeneCards: [1]
Orthologs
SpeciesHumanMouse
Entrez

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Ensembl

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UniProt

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RefSeq (mRNA)

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RefSeq (protein)

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Location (UCSC)n/an/a
PubMed searchn/an/a
Wikidata
View/Edit Human

AQP2 is found in the apical cell membranes of the kidney's collecting duct principal cells and in intracellular vesicles located throughout the cell.

Regulation

It is the only aquaporin regulated by vasopressin.[1] The basic job of aquaporin 2 is to reabsorb water from the urine while its being removed from the blood by the kidney. Aquaporin 2 is in kidney epithelial cells and usually lies dormant in intracellular vesicle membranes. When it is needed, vasopressin binds to the cell surface vasopressin receptor thereby activating a signaling pathway that causes the aquaporin 2 containing vesicles to fuse with the plasma membrane, so the aquaporin 2 can be used by the cell.[2] This aquaporin is regulated in two ways by the peptide hormone vasopressin:

  • short-term regulation (minutes) through trafficking of AQP2 vesicles to the apical region where they fuse with the apical plasma membrane
  • long-term regulation (days) through an increase in AQP2 gene expression.

This aquaporin is also regulated by food intake. Fasting reduces expression of this aquaporin independently of vasopressin.

Clinical significance

Mutations in this channel are associated with nephrogenic diabetes insipidus, which can be autosomal dominant or recessive. Mutations in the vasopressin receptor cause a similar X-linked phenotype.

Lithium, which is often used to treat bipolar disorder, can cause acquired diabetes insipidus (characterized by the excretion of large volumes of dilute urine) by decreasing the expression of the AQP2 gene.

The expression of the AQP2 gene is increased during conditions associated with water retention such as pregnancy and congestive heart failure.

See also

References

  1. ↑ Dibas AI, Mia AJ, Yorio T (December 1998). "Aquaporins (water channels): role in vasopressin-activated water transport". Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine. 219 (3): 183–99. doi:10.3181/00379727-219-44332. PMID 9824541.
  2. ↑ Lodish H, Berk A, Kaiser CA, Krieger M, Scott MP, Bretscher A, Ploegh H, Matsudaira P (2008). Molecular Cell Biology (6th ed.). New York: Freeman. p. 445. ISBN 978-0-7167-7601-7.

Further reading

External links

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