Transient alterations of the blood–brain barrier tight junction and receptor potential channel gene expression by chlorpyrifos
Article first published online: 18 MAY 2012
Copyright © 2012 John Wiley & Sons, Ltd.
Journal of Applied Toxicology
Volume 33, Issue 10, pages 1187–1191, October 2013
How to Cite
Li, W. and Ehrich, M. (2013), Transient alterations of the blood–brain barrier tight junction and receptor potential channel gene expression by chlorpyrifos. J. Appl. Toxicol., 33: 1187–1191. doi: 10.1002/jat.2762
- Issue published online: 26 JUL 2013
- Article first published online: 18 MAY 2012
- Manuscript Revised: 2 MAR 2012
- Manuscript Accepted: 2 MAR 2012
- Manuscript Received: 2 FEB 2012
- blood–brain barrier;
The blood–brain barrier (BBB) is formed by specialized endothelial cells lining capillaries in the central nervous system (CNS). We previously demonstrated that exposure to very low concentrations of the organophosphorus insecticide chlorpyrifos (CPF) decreased electrical resistance across the BBB in vitro, indicating a loss of BBB integrity. The present study examined the transient effects of CPF on expression of genes contributing to tight junctions of the BBB. Rat brain endothelial cells (RBE4) were co-cultured with rat astrocytes on membrane inserts to form an in vitro BBB. The RBE4 cells in the BBB were then exposed to CPF for 2, 4 and 12 h. Total RNA was extracted from RBE4 cells and quantitative real-time PCR (qRT-PCR) was used to quantify levels of gene expression of tight junction proteins claudin5, scaffold proteins zona occludens (ZO1) and transient receptor potential (canonical) channels (TRPC4). Gene expression decreased 2 h after exposure to CPF, especially TRPC4, but the effects were reversed 12 h later. CPF exposure for only 15 min caused less effect than longer exposures, with TRPC4 gene expression above the control at 4 h. These results suggest that altering gene expression for claudin5, TRPC4 and ZO1 by CPF may directly contribute to BBB disruption, and that the alteration is reversible upon removal of CPF. Copyright © 2012 John Wiley & Sons, Ltd.