Inhibitors of NHE-1 Na+/H+ exchange reduce mouse intraocular pressure.

Abstract

The first step in formation of aqueous humor is uptake of NaCl by the ciliary epithelial cells from the stroma, possibly by both paired Na+/H+ and Cl-/HCO3- antiports and a bumetanide-sensitive Na+-K+-2Cl- symport. The present data are consistent with electron probe x-ray microanalyses of rabbit ciliary epithelium indicating that the antiports are the dominant mechanism. That bumetanide can produce a previously unobserved lowering of IOP when the Na+/H+ antiport is also inhibited substantiates a dominant antiport mechanism.