SERUM EFFECTS ON AQUEOUS OUTFLOW DURING ANTERIOR-CHAMBER PERFUSION INMONKEYS

Purpose. To prevent the increase in outflow facility during anterior c hamber perfusion in nonhuman primates by the addition of autologous se rum to Barany's mock aqueous humor. Methods. Total outflow facility wa s measured simultaneously in both eyes of living cynomolgus monkeys fo r 3 hours by two-level constant pressure perfusion of the anterior cha mbers from elevated reservoirs with Barany's solution with (one eye) o r without (opposite eye) 3%, 5%, 10%, or 15% to 20% autologous serum. In other experiments, the anterior chamber contents initially were exc hanged with Barany's solution with (one eye) or without (opposite eye) 5% autologous serum, and the facility response to intravenous pilocar pine was determined. Results. Eyes perfused with serum had a lower sta rting facility than control eyes, with facility decreasing with increa sing serum concentrations, For both groups, facility increased with pe rfusion time and with volume of fluid perfused through the eye, but th e rate of change of facility over time and per change in volume was si gnificantly less for the serum-treated eyes. This difference remained significant when the proportional change of facility relative to basel ine level was analyzed as a function of time but nut as a function of volume. Intravenous infusion of pilocarpine increased facility by appr oximately the same proportion relative to baseline in both groups, but the absolute change and the final facility were lower in the serum-tr eated eyes. Conclusions. Serum or a serum component in the vicinity of the trabecular meshwork normally may help maintain outflow resistance but may be washed away during perfusion with serum-free media.