Experimental retinal detachment. VII. Intravenous horseradish peroxidase diffusion across the blood-retinal barrier
C. B. Toris and J. E. Pederson
Intravenous horseradish peroxidase (HRP) was administered to cynomolgus
monkeys to study chorioretinal diffusion in eyes with retinal detachment.
In control eyes, HRP was contained within the choriocapillaris and did not
penetrate beyond Bruch's membrane. In addition, HRP was confined within
blood vessels of the sensory retina. In detached eyes, HRP diffused out of
the choriocapillaris and through the intercellular spaces of the retinal
pigment epithelium (RPE), where it was blocked by zonulae occludentes.
Occasionally HRP was found within pinocytotic vesicles of the RPE. It was
also confined within retinal blood vessels by their endothelial cells. It
is concluded that the blood-retinal barrier remains intact to HRP following
long-term rhegmatogenous retinal detachment. However, a slight alteration
exists at the choriocapillaris in detached eyes.
