Effects of methyl-beta-cyclodextrin on blood-brain barrier permeability in angiotensin II-induced hypertensive rats

•Acute hypertension increases BBB permeability via caveolae-mediated endocytosis.•MBCD does not have an impact on the disruption of BBB during acute hypertension.•MBCD causes BBB disruption and increases BBB permeability in normotensive rats. The blood-brain barrier (BBB) permeability primarily increases in cerebral venules during acute hypertension. Methyl-β-cyclodextrin (MβCD), a cholesterol-depleting agent, decreases the expression of caveolins disrupting caveolar structures. We aimed to determine the effects of MβCD on the BBB permeability of angiotensin (ANG) II-induced hypertensive rats. Three minutes after MβCD administration (5 mg/kg), acute hypertension was induced by ANG II (60 µg/kg). Evans blue (EB) and horseradish peroxidase (HRP) tracers were used to assess BBB permeability. Immunohistochemistry for caveolin (Cav)-1 and tight junction protein claudin-5 was performed. EB dye content significantly increased in both cerebral cortices and left hippocampus in MβCD (P