Alpha 2.0
Login Register
» Articles » PMID: 14645363

Water Transport Becomes Uncoupled from K+ Siphoning in Brain Contusion, Bacterial Meningitis, and Brain Tumours: Immunohistochemical Case Review

Overview
Journal J Clin Pathol
Specialty Pathology
Date 2003 Dec 4
PMID 14645363
Citations 20
Authors
S Saadoun
M C Papadopoulos
S Krishna
Affiliations
Soon will be listed here.
Abstract

Specimens of normal human brain, contused brain, brain with bacterial meningitis, and brain tumours were immunolabelled for aquaporin 4 (AQP4) and Kir4.1. In normal brain tissue, AQP4 and Kir4.1 were detected around the microvessels. In pathological brain tissue, AQP4 was upregulated in astrocytes in oedematous regions and Kir4.1 was upregulated in astrocytes in damaged brain. Changes in alpha syntrophin expression paralleled those of AQP4 and Kir4.1. The following hypothesis is proposed: in astrocytes, under normal conditions, AQP4 couples water transport with Kir4.1 mediated K+ siphoning, but in pathological states, AQP4 facilitates the flow of brain oedema fluid, and Kir4.1 buffers increased extracellular K+.

Citing Articles

Exploring Aquaporins in Human Studies: Mechanisms and Therapeutic Potential in Critical Illness.

Vrettou C, Issaris V, Kokkoris S, Poupouzas G, Keskinidou C, Lotsios N Life (Basel). 2025; 14(12.

PMID: 39768394 PMC: 11676363. DOI: 10.3390/life14121688.

Astragalus polysaccharide ameliorates diabetic retinopathy by inhibiting the SHH-Gli1-AQP1 signaling pathway in streptozotocin-induced type 2 diabetic rats.

Qu J, Wang B, Wang Y, Li H, An X Korean J Physiol Pharmacol. 2024; 29(1):21-32.

PMID: 39539170 PMC: 11694010. DOI: 10.4196/kjpp.23.251.

Aquaporin-4 expression and modulation in a rat model of post-traumatic syringomyelia.

Berliner J, Lam M, Najafi E, Hemley S, Bilston L, Stoodley M Sci Rep. 2023; 13(1):9662.

PMID: 37316571 PMC: 10267129. DOI: 10.1038/s41598-023-36538-x.

Blood-Brain Barrier Alterations and Edema Formation in Different Brain Mass Lesions.

Solar P, Hendrych M, Barak M, Valekova H, Hermanova M, Jancalek R Front Cell Neurosci. 2022; 16:922181.

PMID: 35910247 PMC: 9334679. DOI: 10.3389/fncel.2022.922181.

Selective mGluR1 Negative Allosteric Modulator Reduces Blood-Brain Barrier Permeability and Cerebral Edema After Experimental Subarachnoid Hemorrhage.

Zhang C, Jiang M, Wang W, Zhao S, Yin Y, Mi Q Transl Stroke Res. 2019; 11(4):799-811.

PMID: 31833035 DOI: 10.1007/s12975-019-00758-z.

References
1.
Manley G, Fujimura M, Ma T, Noshita N, Filiz F, Bollen A . Aquaporin-4 deletion in mice reduces brain edema after acute water intoxication and ischemic stroke. Nat Med. 2000; 6(2):159-63. DOI: 10.1038/72256. View
2.
Li L, Head V, Timpe L . Identification of an inward rectifier potassium channel gene expressed in mouse cortical astrocytes. Glia. 2001; 33(1):57-71. DOI: 10.1002/1098-1136(20010101)33:1<57::aid-glia1006>3.0.co;2-0. View
3.
Papadopoulos M, Saadoun S, Davies D, Bell B . Emerging molecular mechanisms of brain tumour oedema. Br J Neurosurg. 2001; 15(2):101-8. DOI: 10.1080/02688690120036775. View
4.
Higashi K, Fujita A, Inanobe A, Tanemoto M, Doi K, Kubo T . An inwardly rectifying K(+) channel, Kir4.1, expressed in astrocytes surrounds synapses and blood vessels in brain. Am J Physiol Cell Physiol. 2001; 281(3):C922-31. DOI: 10.1152/ajpcell.2001.281.3.C922. View
5.
Neely J, Amiry-Moghaddam M, Ottersen O, Froehner S, Agre P, Adams M . Syntrophin-dependent expression and localization of Aquaporin-4 water channel protein. Proc Natl Acad Sci U S A. 2001; 98(24):14108-13. PMC: 61176. DOI: 10.1073/pnas.241508198. View