Effects of Antiglaucoma Drugs on Calcium Mobility in Cultured Corneal Endothelial Cells

The aim of this study was to estimate the effects of various antiglaucoma drugs including betaxolol, timolol, levobunolol, brimonidine, carteolol, dipivefrin, dorzolamide, brinzolamide, latanoprost, unoprostone, and pilocarpine on intracellular free Ca2+ ([Ca2+]i) mobility in cultured bovine corneal endothelial cells. Various antiglaucoma drugs were diluted from original concentrations to 1/100, 1/1,000, and 1/10,000. The [Ca2+]i mobility was studied by spectrofluorophotometry after loading with the ester of fura-2 (fura-2/AM). It was found that timolol (58 μM and 5.8 μM), levobunolol (171 μM, 17.1 μM, and 1.71 μM), betaxolol (162 μM, 16.2 μM, and 1.62 μM), carteolol (680 μM and 68 μM), dipivefrin (28 μM and 2.8 μM), dorzolamide (616 μM and 61.6 μM), brinzolamide (260 μM), latanoprost (1.1 μM), unoprostone (28.2 μM, 2.82 μM, and 0.282 μM), and pilocarpine (408 μM and 40.8 μM) induced a significant increase in [Ca2+]i. Nevertheless, only brimonidine (68 μM and 6.8 μM) decreased [Ca2+]i concentration significantly. Benzalkonium chloride preservative did not affect [Ca2+]i after addition of 0.001, 0.0001 and 0.00001 mg/mL to cells. These results indicate that all antiglaucoma drugs may affect the physiologic function of corneal endothelial cells through change of [Ca2+]i.mobility.