Cocaine-mediated disruption of ZO-1 expression involves PDGF-BB. (A) Exposure of HBMECs to cocaine resulted in time-dependent decrease in expression of ZO-1. (B) Cocaine-mediated decrease of ZO-1 expression was ameliorated by pretreating the cells with the PDGF-BB neutralizing antibody. (C) Exposure of HBMECs to PDGF-BB resulted in a time-dependent decrease in ZO-1 expression. (D) Cocaine-mediated increase in BBB permeability was ameliorated in HBMECs pretreated with the PDGF-BB neutralizing antibody. All the data are presented as mean ± SD of 4 separate experiments. **P < .01, ***P < .001 vs control group; ##P < .01 vs cocaine-treated group.