Abstract
Carotid artery injection of Evans Blue or albumin-bound bilirubin (ALB+BR) for 60 sec. in adult rats produced no cortical staining with an intact blood-brain barrier(BBB) and non-uniform “tufted” perivascular staining after barrier opening to ALB by 1.8 Molar Urea × 30 sec. Unbound BR given for 10-60 sec. to 25 rats without barrier opening, followed by carotid perfusion with saline, produced uniform staining, and the uptake of BR measured by chloroform extraction was dose-dependent (r=0.641, p<0.001). Retained BR was 11.6±6.2% (MEAN±S.D.) of the dose injected, and the permeability-surface area (P.S) product for BR was 0.13±0.05 ml·min−1 · g−1. The estimated volume of distribution for unbound BR at 60 sec. was 195±72 μl/g. When injection of unbound BR was followed by re-infusion with 5% ALB, residual brain BR decreased as shown:
Bound BR crossing a disrupted BBB and unbound BR crossing an intact barrier appear to have different extravascular patterns of distribution, consistent with the greater lipid solubility and capillary permeability of unbound BR, versus the tendency of ALB + BR to cross the barrier only at osmotically opened capillaries. Because ALB decreases residual brain BR, we speculate that BR is initially distributed in a “shallow” compartment and is not immediately strongly bound or irreversibly precipitated in the brain.
Log in or create a free account to read this content
Gain free access to this article, as well as selected content from this journal and more on nature.com
or
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Cashore, W., Blazar, P. 1359 BILIRUBIN (BR) FLUX AND DISTRIBUTION IN THE BRAIN. Pediatr Res 19, 337 (1985). https://doi.org/10.1203/00006450-198504000-01383
Issue date:
DOI: https://doi.org/10.1203/00006450-198504000-01383
