Blood-brain barrier breakdown occurs early after traumatic brain injury and is not related to white blood cell adherence.

Publication Type	Academic Article
Authors	Härtl R, Medary M, Ruge M, Arfors K, Ghajar J
Journal	Acta Neurochir Suppl
Volume	70
Pagination	240-2
Date Published	01/01/1997
ISSN	0065-1419
Keywords	Blood-Brain Barrier, Brain Injuries, Leukocytes
Abstract	The time course of blood-brain barrier (BBB) breakdown after traumatic brain injury (TBI) has important implications for therapy. This study was conducted in order to test post-traumatic BBB dysfunction in a model of fluid-percussion induced TBI in rabbits at 1 and 6 hours after TBI and relate it to white blood cell (WBC) activation. Ten anesthetized rabbits had chronic cranial windows implanted three weeks prior to experimentation. Fluid-percussion injury (3.5 atm.) was induced and animals were followed for 1 or 6 h. Intravital fluorescence videomicroscopy was used to assess BBB permeability and WBC adhesion to pial venules. Na(+)-fluorescein was infused continuously over 30 min at either 30 min (Group I, n = 5) or 5.5 h (Group II, n = 5) after TBI. Microvascular permeability in individual postcapillary venules was assessed qualitatively at 1 and 30 min after start of infusion. TBI led to a transient mean arterial blood pressure (MAP) surge after trauma and a progressive increase in the number of sticking WBCs per mm2 vessel wall. Na(+)-fluorescein extravasation was observed in 4 out of 5 Group I animals and in none of Group II. BBB breakdown was not associated with WBC sticking. We conclude that after fluid-percussion injury the BBB is damaged at 1 h post-trauma and that its function is restored 6 h later. Increased WBC sticking at 6 h is not associated with BBB breakdown. Whether WBCs may cause vascular permeability changes at a later point needs further investigation.
DOI	10.1007/978-3-7091-6837-0_74
PubMed ID	9416334