BBB properties in the neonatal and adult <i>in vitro</i> BBB models.

<p>The TEER (A), the permeability of Na-F (B) and EBA (C), and the influx (luminal-to-abluminal) and efflux (abluminal-to-luminal) of rhodamine 123 (D) in the neonatal (2 weeks, filled columns) and adult (8 weeks, open columns) BBB models. Inset in panel D shows the effect of verapamil on rhodamine 123 influx in both models. Data are means ± SEM (n = 11−12 from 3 separate experiments (A, B, and C), n = 12−19 from 3–5 separate experiments (D); n = 8−20 from 2–5 separate experiments (Fig. D inset)). ^**<i>P</i><0.01, significantly different from the neonatal BBB model. ^#<i>P</i><0.05, ^##<i>P</i><0.01, significantly different from the influx of rhodamine 123.⁺⁺<i>P</i><0.01, significantly different from each corresponding control.