Ocular vascular permeability. Effect of systemic administration of bacterial endotoxin.

Abstract

Intravenously administered bacterial endotoxin induces an acute marked alteration in ocular vascular permeability in the rabbit. This effect was measured using a dual radioisotope technique employing red blood cells labeled with Ferrie chloride Fe 59 and human serum albumin labeled with iodine 131. Sites of vascular leakage were identified by a topographic analysis utilizing carbon particles systemically. Ocular blood volume was unchanged until 12 hours after endotoxin when a 50% rise was noted. Extravascular protein (extravascular albumin space—EVAS) was seven times greater than in the normal rabbit at two to four hours, twice as great at 12 hours, and was returning to normal at 24 hours. Leakage was primarily in ciliary processes, and by 12 hours, these were markedly edematous. The HSA 131 I content in the aqueous was only a partial indication of the extent of the vascular permeability change.