The choroid plexus in rats exhibited ultrastructural changes following a non-penetrative blast. The immunophenotypic features of epiplexus cells associated with the choroid plexus epithelium were also altered. In rats killed at 1 and 7 days after the blast, the intercellular spaces between the epithelial cells were greatly widened, coupled with the massive eruption and possible extrusion of the...

It has been proposed that either the Igf-2 gene or the H19 gene--but not both--can be expressed from a given chromosome. Igf-2 is known to be biallelically expressed in the choroid plexus and leptomeninges, however, raising the question of whether H19 is down-regulated or absent there. We found by in situ hybridization that H19 is indeed expressed in the choroid plexus and leptomeninges of the ...

Recent observations have suggested that lentiviruses stimulate the proliferation and activation of microglia. A similar effect within the dense macrophage population of the choroid plexus could have signiŽcant implications for trafŽcking of virus and inammatory cells into the brain. To explore this possibility, we cultured fetal feline macrophages and examined their response to feline immunode...

Several studies suggest the involvement of Na+ and HCO3- transport in the formation of cerebrospinal fluid. Two Na+-dependent HCO3- transporters were recently localized to the epithelial cells of the rat choroid plexus (NBCn1 and NCBE), and the mRNA for a third protein was also detected (NBCe2) (Praetorius J, Nejsum LN, and Nielsen S. Am J Physiol Cell Physiol 286: C601-C610, 2004). Our goal wa...

beta-Amyloid (Abeta) concentration in the cerebrospinal fluid (CSF) of the brain may be regulated by the choroid plexus, which forms a barrier between blood and brain CSF. Abeta uptake from CSF was determined as its volume of distribution (V(D)) into isolated rat choroid plexus tissue. The V(D) of [125I]Abeta1-40 was corrected by subtraction of the V(D) of [14C]sucrose, a marker for extracellul...

Both adult liver and choroid plexus express the organic anion transport protein (oatp1) and transport [35S]bromosulfophthalein (BSP). Studies of the developing rat liver reveal that oatp1 mRNA and protein do not begin to be expressed until 15 days postnatal and are at adult levels by 30 days. Uptake of [35S]BSP follows the same time course. In contrast, neonatal rat choroid plexus expresses oat...

To treat human immunodeficiency virus (HIV) within the central nervous system (CNS), levels of anti-HIV drugs in the brain must reach therapeutic concentrations. The ability of (-)-2'-deoxy-3'-thiacytidine (3TC; lamivudine) to cross the blood-brain and blood-cerebrospinal fluid (CSF) barriers, alone and in combination with additional nucleoside analogs, was investigated. The bilateral in situ g...

Levels of transferrin mRNA were measured by hybridization to transferrin cDNA in extracts from various areas of rat brain and other tissues. The highest concentrations of transferrin mRNA were found in the liver and the choroid plexus of the lateral and third ventricles. Lower concentrations were observed in the medulla and thalamus, choroid plexus of the fourth ventricle, cortex, hypothalamus,...

The choroid plexus actively transports endogenous, xenobiotic, and therapeutic compounds from cerebrospinal fluid to blood, thereby limiting their exposure to the central nervous system (CNS). Establishing the mechanisms responsible for this transport is critical to our understanding of basic choroid plexus physiology and will likely impact drug targeting to the CNS. We recently generated an or...

The molecular mechanisms underlying regulation of fluid production by secretory epithelia such as the choroid plexus are poorly understood. Two cAMP-regulated inhibitors of protein phosphatase-1, inhibitor-1 (I1) and a dopamine- and cAMP-regulated phosphoprotein, M(r) = 32,000 (DARPP-32), are enriched in the choroid plexus. We show here that these two phosphoproteins are colocalized in choroid ...