title: Experimental colitis increases blood-brain barrier permeability in rabbits.
abstract: Extraintestinal manifestations of inflammatory bowel disease are numerous. This study examined the effects of two models of acute colitis on cerebral blood flow (CBF) and permeability of the blood-brain barrier in rabbits. CBF (measured with radiolabeled microspheres), or the extraction ratio or permeability-surface area (PS) product of the blood-brain barrier to fluorescein and FITC-dextran, was measured 48 h after colitis induction with acetic acid (HAc) or trinitrobenzene sulfonic acid (TNBS). PS product for fluorescein increased (P < 0.05) in TNBS colitis (1.33 x 10(-5) +/- 0.52 x 10(-5) ml/s and 0.48 x 10(-5) +/- 0.13 x 10(-5) ml/s (mean +/- SE) for treated (n = 14) and untreated (n = 10) animals, respectively. PS product for the larger FITC-dextran was not different in TNBS colitis (0.24 x 10(-5) +/- 0.09 x 10(-5) ml/s, n = 7) compared with untreated controls (0.19 x 10(-5) +/- 0.04 x 10(-5) ml/s, n = 8). PS product for fluorescein increased (P < 0.01) in HAc colitis compared with vehicle (2.66 x 10(-5) +/- 1.46 x 10(-5) ml/s and 0.33 x 10(-5) +/- 0.05 x 10(-5) ml/s, respectively; n = 6 in each group). The extraction of fluorescein from the blood to the brain increased by 75% during TNBS colitis when compared with vehicle (P < 0.05). CBF and cerebrovascular resistance did not change from the untreated control after TNBS colitis. Our data suggest that, irrespective of induction method, acute colitis increases the permeability of the blood-brain barrier to small molecules without changing CBF.
mesh_terms: D019342:Acetic Acid; D000818:Animals; D001794:Blood Pressure; D001812:Blood-Brain Barrier; D001921:Brain / Q000098:blood supply; D002199:Capillary Permeability; D002560:Cerebrovascular Circulation; D003092:Colitis / Q000139:chemically induced / Q000503:physiopathology*; D003911:Dextrans; D019793:Fluorescein; D016650:Fluorescein-5-isothiocyanate / Q000031:analogs & derivatives; D008297:Male; D008863:Microspheres; D011817:Rabbits; D014302:Trinitrobenzenesulfonic Acid; D014655:Vascular Resistance