To study the regulation of the ion transport mechanisms that drive aqueous humor secretion we use porcine eyes to measure the actual rate of fluid production. The intact eye is cannulated at the ciliary artery and perfused with solution. The aqueous humor compartment is filled with fluorescein. New aqueous humor enters the eye, diluting the fluorescein concentration. Aqueous formation is calculated from the rate of dilution.
This whole eye preparation lets us measure the effects of drugs on aqueous formation. These include ouabain, carbonic anhydrase inhibitors and compound that affect signaling molecules like nitric oxide.