Aqueous humor turnover rates in the cat. II. Effect of ouabain and chlorothiazide.

.he ability of the cardiac glycosides, ouabain and digoxin, to lower eye pressure-' '' '-• has been ascribed to a primary inhibition of aqueous humor inflow. In the cat, which is the experimental animal of this study, the effect of ouabain on aqueous humor inflow is not clear. The previous report, which indicated that aqueous humor formation of the cat was decreased by ouabain, was based upon rates of recovery of eye pressure after aspiration of some of the anterior chamber fluid. In essence, no distinction could be made of the ouabain effect on primary aqueous humor which is secreted and that of secondary aqueous humor which is generally considered as an ultrafiltrate. This report concerns the effect of ouabain on the turnover rates of intracamerally injected inulin under conditions of steady state. The diuretic, chlorothiazide, which has been demonstrated to have no effect on aqueous humor formation lj 5> s was used as a control.