Studies on vascular permeability changed in experimental brain concussion. II. Duration of altered permeability

An ultrastructural study of experimental high velocity penetrating head injury

Experimental high velocity missile brain injury in the rhesus monkey produces widespread swelling of perivascular astrocytes within 30 min of injury. Possible mechanisms for this lesion include a direct effect of force, chemical mediation secondary to the extravasation of blood, alterations in the permeability of the blood brain barrier and ischaemia. The implications of this findings for the function of the blood brain barrier, for neurotransmission and for neuronal survival are discussed.

Chronic relapsing experimental allergic encephalomyelitis. Studies in vascular permeability changes

The vascular permeability in the nervous system to Evans blue-albumin and horseradish peroxidase was studied in chronic relapsing EAE in strain 13 and Hartley guinea pigs. The disease was induced by single sensitization of immature animal and was characterized clinically by remissions and relapses. Recent and old demyelinating plaques in the spinal cord were present. These showed an increased permeability to the protein tracers. The blood-brain barrier in these plaques are therefore disturbed and also in this respect the condition is similar to the multiple sclerosis lesions.