REVERSIBLE BLOOD-BRAIN-BARRIER DYSFUNCTION TO PEROXIDASE AFTER A SMALL STAB WOUND IN RAT CEREBRAL-CORTEX

  • 1 January 1976
    • journal article
    • research article
    • Vol. 35  (4) , 333-342
Abstract
Small stab wounds were made in the rat frontal lobe. The animals were injected with horseradish peroxidase i.v. at different times after the injury to study the extravasation of this tracer. There was a leakage of peroxidase into the brain during the first 3 days after the injury. The route of passage from the vessel lumen into the brain was through disrupted blood vessels in the injured region. Endothelial pinocytosis and formation of thin, trans-endothelial channel-like structures with or without a content of peroxidase were 2 other possible routes of passage across the blood vessels. Occasionally, badly damaged endothelial cells displayed a diffuse cytoplasmic distribution of peroxidase, indicating a diffusion into and possibly across these injured cells. No widened tight junctions were seen. This study indicated 4 possible routes of passage of horseradish peroxidase across the endothelial cells: cellular gross damage with disrupture of the cells, diffusion across badly injured endothelial cells, possibly pinocytosis and formation of trans-endothelial channel-like structures. The cellular uptake of the tracer was vesicular in most neurons, astrocytes, oligodendrocytes and hematogeneous phagocytes. A diffuse distribution of the tracer was seen in some dark neurons near leaking vessels in the vicinity of the stab wound.