Amiloride inhibition of Na+-entry into corneal endothelium.

Amiloride in 10(-3) M concentration inhibits incompletely the short circuit current and active potential difference across the bovine corneal endothelium in vitro. The drug effect is reversible and unilateral, e.g. the drug is effective only from the aqueous side. The amiloride effect is compared to the effect of ouabain, nystatin and vasopressin on the same electrical parameters. The effect of these drugs support a model for active Na+ transport across the corneal endothelium with two separate pathways for Na+ transport - one for extrusion and one for reentry.