Circulating immune complexes. Effects on ocular vascular permeability in the rabbit

E. L. Howes Jr and D. G. McKay

Sudden transient, alteration in vascular permeability is producible in rabbit eyes by intravenous injection of large quantities of antigen, bovine gamma-globulin (BGG), into immunized animals or by intravenous injection of large amounts of antigen-antibody complexes (BGG-antiBGG) prepared in antigen excess (20 to 25times) in normal rabbits. Change is measured by ocular accumulation of iodinated I125 serum albumin, relative to that in heart blood, in intact eyes and separate anatomical compartments, in aqueous, in the anterior eye including (lens plus vitreous), and in the posterior segment. Primarily affected are vessels in the iridial portion of ciliary processess; edema is the primary finding. The same vessels are affected by intravenous injection of bacterial endotoxin, but compared with endotoxin, altered vascular permeability is short-lived and is not associated with formation of platelet plugs and intravenous fibrin strands.