Aging affects choroidal proteins involved in CSF production in Sprague-Dawley rats.

Aging is currently associated with progressive declines of cerebral functions. From these, a decreased resistance to dehydration suggested alteration in choroidal control of brain homeostasis and reduced cerebrospinal fluid (CSF) production in old subjects. In the present study, choroid plexuses of 20-month old Sprague-Dawley rats were compared with those of 3- and 10-month old rats.

Expression of P-glycoprotein (ABCB1) and Mrp1 (ABCC1) in adult rat brain: focus on astrocytes.

P-glycoprotein (P-gp, ABCB1) and the multidrug resistance-associated protein 1 (Mrp1, ABCC1) are two ATP-driven pumps that mediate the export of organic anions from cells and may confer cellular resistance to many cytotoxic hydrophobic drugs. Immunohistochemistry has shown that P-gp is expressed in rat brain capillary vessels forming the blood-brain barrier (BBB). Mrp1 mRNAs have been detected by RT-PCR in rat brain isolated capillaries.

CSF-contacting epithelia in altered gravity: changes in apical structures and water channels expression.

Apical cytoskeletal structures and water channels are affected in both choroidal and ependymal cells lining the cerebral ventricles. Structural alterations and changes in expression of AQPI and AQP4, evaluated by immuno-cytochemistry and in situ hybridization confirm the impact of variations in gravity in CSF-lining epithelia.

Influence of hypergravity on hypothalamic vasopressin and oxytocin neurons in rats.

This study was aimed to evaluate the reaction of the vasopressin (VP) and oxytocin (OT) neurons of the supraoptic nucleus (SON) in rats to single or repeated hypergravity (HG). Special attention was paid to the tyrosine hydroxylase (TH) expression in VP neurons as a marker of the neuron activation. Rats were revolved in a centrifuge with overloading 2G for 5 days or 34 days as well as for 34 days plus 5 days with an interval of 39 days between two rotations.

P-glycoprotein (ABCB1) but not multidrug resistance-associated protein 1 (ABCC1) is induced by doxorubicin in primary cultures of rat astrocytes.

At least two drug efflux pumps involved in multidrug resistance, P-glycoprotein (P-gp) and multidrug resistance-associated protein 1 (Mrp1), are expressed in rat astrocyte primary cultures. The aim of this study was to compare the expression of P-gp and Mrp1 in primary cultures exposed to 50 or 500 ng/mL doxorubicin (DOX). Among the two P-gp genes expressed in rodents, mdr1a and mdr1b, a time- and dose-dependent increase in mdr1b mRNA levels was revealed by northern blot analysis.