Choroidal epithelial cells

Primary cultured cerebral endothelial cells, immortalized cell line Primary cultured choroid epithelial cells, immortalized cell line... 

MRP4 is abundantly expressed in the kidney followed by the liver (238,260). The membrane localization of Mrp4 is tissue dependent sinusoidal membrane in the hepatocytes (261), brush border membrane of the renal tubules (262,263), luminal membrane of the brain capillaries (262), and basolateral membrane of the choroid epithelial cells (262). 

Figure 3.1. Schematic representation of the cellular components of the blood-hrain (Panel A) and blood-cerehral spinal fluid (Panel B) barriers. The blood-brain barrier consists of continuous type endothelial cells with complex tight junctions to limit paracellular diffusion. The astrocytes and pericytes located in close proximity to the brain endothelial cells release various endogenous factors that modulate endothelial cell permeability. In contrast, the choroid endothelial cells are fenestrated and the blood-cerebral spinal fluid barrier properties are provided by the tight junctions formed between the choroid epithelial cells.

FIGURE 5-3 Immunocytochemical localization of the Na,K pump in choroid plexus. Choroid plexus contains epithelial cells with intensely stained microvillar and intermicrovillar plasma membranes. The basal and lateral plasma membrane surfaces are not stained. Bar = 2 im. (With permission from reference [81].)... 

Transferrin is an iron carrier protein that acts as a trophic survival factor for neurons, astrocytes and OLs. As the blood-brain barrier becomes established during development, neural cells become dependent on transferrin produced by OLs and choroid plexus epithelial cells (Fig. 25-14). OLs are the major source of transferrin in the CNS. This suggests an important function for OLs in... 

The S-HTjc receptor has highest density in the choroid plexus on epithelial cells associated with production of cerebrospinal fluid (Razos and Palacios 1985]. 5-HT2C receptors are also found in the cingulate cortex, hippocam-... 

Tire brain, which must function in a chemically stable environment, is protected by a tough outer covering, the arachnoid membrane, and by the blood-brain barrier406 407 and the blood-cerebrospinal barrier. Both of these barriers consist of tight junctions similar to those seen in Fig. 1-15A. They are formed between the endothelial cells of the cerebral capillaries and between the epithelial cells that surround the capillaries of the choroid plexus. The choroid plexus consists of capillary beds around portions... 

In addition, the epithelial cells of the choroid plexus facing the cerebrospinal fluid (CSF) constitute the blood-cerebrospinal fluid barrier (BCSFB). The BCSFB is also a significant area for exchange between the blood and the CSF. In rats the total calculated surface area of the choroid plexus is about 33% of that of the BBB [2]. In humans, based on the relative mass of the choroid plexus in comparison with the brain, the relative surface area of the choroid plexus may be in the region of 10% of that of the BBB. The CSF is secreted across the choroid plexus epithelial cells into the brain ventricular system [3] the remainder of the brain extracellular fluid (ECF) and the interstitial fluid (ISF) are secreted at the capillaries of the BBB themselves [4]. The ratio of fluid production from these sites is 40% 60%, respectively [5],... 

The BBBs to macromolecules and most polar solutes are created by the formation of tight junctions between the cerebral endothelial cells, the choroid plexus epithelial cells, and the cells of the arachnoid membrane. These tight junctions are a key feature of the BBB and effectively abolish any aqueous paracellular diffusional pathways between the endothelial cells from the blood plasma, or somatic ECF, to the brain ECF. This removal of the paracellular pathway efficiently prevents the free diffusion of polar solutes from blood to brain [11],... 

Shu C, Shen H, Teuscher NS, Lorenzi PJ, Keep RF, Smith DE. Role of PEPT2 in pep tide/mimetic trafficking at the blood-cerebrospinal fluid barrier studies in rat choroid plexus epithelial cells in primary culture. J Pharmacol Exp Ther 2002 301 820-829. 

A subset of FRAPs and 5-HT receptors share ultrastructural similarities, suggesting their close proximities in specialized subcellular regions. Confocal and electron microscopy demonstrated a concentration of 5-HT2C receptors in the microvilli bordering the apical surface of the epithelial cells in the choroids plexus where they colocalize with Veli-3 and MUPP1, both of which have been... 

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