BBB permeability in multiple brain regions during the chronic stage of inflammatory dural stimulation. (a) BBB permeability (as measured by the ratio of fluorescence from sodium fluorescein uptake in the brain region in comparison to serum levels) in naive (N = 8), saline–infused (N = 7), and IS infused (N = 8) rats in the TNC. (b) BBB permeability in naive (N = 8 for each group), saline infused (N = 8 for each group), and IS infused (N = 8 for each group) rats in the frontal cortex and sub-cortex. (c) BBB permeability in naive (N = 7), saline infused (N = 7), and IS infused (N = 7) rats in the PAG. (d) BBB permeability at the site of the infusion (infusion- cortex) in saline (N = 8) and inflammatory soup infused (N = 7) rats.
TNC: trigeminal nucleus caudalis; PAG: periaqueductal grey; IS: inflammatory soup; BBB: blood-brain barrier. *p < 0.05. BBB permeability is expressed as brain:serum ratio.