Table 1.

The effects of drugs of abuse on the BBB.

	Cocaine	Morphine	Methamphetamine
TEER value	Decrease (Fiala et al. 2005)	Decrease (Mahajan et al. 2008)	Decrease (Ramirez et al. 2005)
Barrier permeability	Increase monocyte transmigration and FITC-D passage (Fiala et al. 1998; Fiala et al. 2005; Gan et al. 1999)	Increase PBMC transmigration (Mahajan et al. 2008)	Increased Na-F passage (Ramirez et al. 2005; Banerjee et al. 2010)
Cytokines and Chemokines	Increase MCP-1 (Dhillon et al. 2008; Yao et al. 2010), CCR2 (Dhillon et al. 2008), TNF-α, IL-6 (Gan et al. 1999)	Increase TNF-α and IL-8 secretion (Mahajan et al. 2008)	ND
Interendothelial gap formation	Increase (Fiala et al. 2005)	ND	Increase (Ramirez et al. 2009)
ZO-1 protein stability	Decrease (Dhillon et al. 2008)	ND	ND
TJ protein expression	ND	Decrease ZO-1 and occludin (from RNA level) (Mahajan et al. 2008)	Decrease ZO-1, claudin-5, and occludin (Ramirez et al. 2005; Banerjee et al. 2010)
ROS production	ND	ND	Increase (Banerjee et al. 2010; Kiyatkin and Sharma 2009)
Synergy	Tat (Ghandi et al. 2010)	Tat (Mahajan et al. 2008)	Tat, gpl20 (Banerjee et al. 2010)

transendothelial electrical resistance (TEER), zonula occludens 1 (ZO-1), tight junctions (TJ), reactive oxygen species (ROS), tumor necrosis factor α (TNF-α), sodium-fluorescein (Na-F), FITC-dextran (FITC-D)