TY - JOUR

T1 - Dual function of the choroid plexus

T2 - Cerebrospinal fluid production and control of brain ion homeostasis

AU - MacAulay, Nanna

AU - Toft-Bertelsen, Trine L.

N1 - Publisher Copyright: © 2023 The Author(s)

PY - 2023

Y1 - 2023

N2 - The choroid plexus is a small monolayered epithelium located in the brain ventricles and serves to secrete the cerebrospinal fluid (CSF) that envelops the brain and fills the central ventricles. The CSF secretion is sustained with a concerted effort of a range of membrane transporters located in a polarized fashion in this tissue. Prominent amongst these are the Na+/K+-ATPase, the Na+,K+,2Cl− cotransporter (NKCC1), and several HCO3− transporters, which together support the net transepithelial transport of the major electrolytes, Na+ and Cl−, and thus drive the CSF secretion. The choroid plexus, in addition, serves an important role in keeping the CSF K+ concentration at a level compatible with normal brain function. The choroid plexus Na+/K+-ATPase represents a key factor in the barrier-mediated control of the CSF K+ homeostasis, as it increases its K+ uptake activity when faced with elevated extracellular K+ ([K+]o). In certain developmental or pathological conditions, the NKCC1 may revert its net transport direction to contribute to CSF K+ homeostasis. The choroid plexus ion transport machinery thus serves dual, yet interconnected, functions with its contribution to electrolyte and fluid secretion in combination with its control of brain K+ levels.

AB - The choroid plexus is a small monolayered epithelium located in the brain ventricles and serves to secrete the cerebrospinal fluid (CSF) that envelops the brain and fills the central ventricles. The CSF secretion is sustained with a concerted effort of a range of membrane transporters located in a polarized fashion in this tissue. Prominent amongst these are the Na+/K+-ATPase, the Na+,K+,2Cl− cotransporter (NKCC1), and several HCO3− transporters, which together support the net transepithelial transport of the major electrolytes, Na+ and Cl−, and thus drive the CSF secretion. The choroid plexus, in addition, serves an important role in keeping the CSF K+ concentration at a level compatible with normal brain function. The choroid plexus Na+/K+-ATPase represents a key factor in the barrier-mediated control of the CSF K+ homeostasis, as it increases its K+ uptake activity when faced with elevated extracellular K+ ([K+]o). In certain developmental or pathological conditions, the NKCC1 may revert its net transport direction to contribute to CSF K+ homeostasis. The choroid plexus ion transport machinery thus serves dual, yet interconnected, functions with its contribution to electrolyte and fluid secretion in combination with its control of brain K+ levels.

KW - Cerebrospinal fluid

KW - Choroid plexus

KW - Ionic gradients

KW - K homeostasis

KW - Membrane transport

KW - Na/K-ATPase

U2 - 10.1016/j.ceca.2023.102797

DO - 10.1016/j.ceca.2023.102797

M3 - Journal article

C2 - 37801806

AN - SCOPUS:85173253199

VL - 116

JO - Cell Calcium

JF - Cell Calcium

SN - 0143-4160

M1 - 102797

ER -