Distribution of a putative endothelial barrier antigen in the ocular and orbital tissues of the rat.
BACKGROUND
A rat endothelial barrier antigen (EBA) recognised by a monoclonal antibody has been shown to be expressed strongly by endothelial cells of brain capillaries possessing a blood-brain barrier and only weakly expressed by fenestrated brain vessels.


METHODS
In this study immunocytochemical methods for light and electron microscopy were used to study EBA distribution in the eye and orbital tissues of the rat.


RESULTS
Blood-ocular barrier vessels in the optic nerve, retina, iris, and some vessels in th choroid and ciliary body were immunopositive for EBA. By pre-embedding immunocytochemistry for electron microscopy the antigen was observed on the luminal endothelial cell surface.


CONCLUSIONS
Surprisingly, some non-barrier vessels in the ciliary body and choroid expressed EBA suggesting that it may play a broader role in endothelial properties than previously recognised. The functional significance of EBA remains to be elucidated.
Lawrenson
J G
JG
Reta Lila Weston Institute of Neurological Studies, University College London Medical School.
Ghabriel
M N
MN
Reid
A R
AR
Gajree
T N
TN
Allt
G
G
D000818:Animals; D000954:Antigens, Surface / Q000032:analysis*; D001812:Blood-Brain Barrier / Q000276:immunology*; D002829:Choroid / Q000276:immunology; D002924:Ciliary Body / Q000276:immunology; D005123:Eye / Q000276:immunology*; D007150:Immunohistochemistry; D007498:Iris / Q000276:immunology; D008297:Male; D016253:Microscopy, Immunoelectron; D009900:Optic Nerve / Q000276:immunology; D009915:Orbit / Q000276:immunology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012160:Retina / Q000276:immunology
D000954:Antigens, Surface