THE INFLUENCE OF THE CARDIAC GLYCOSIDE OUABAIN ON THE INTRAOCULAR PRESSURE AND DYNAMICS OF THE RABBIT AND THE CAT

¹ Ophthalmological Research Unit, Wilmer Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland

A study has been made of the effect of the cardiac glycoside ouabain on the intraocular pressure and the aqueous humor dynamics of the rabbit and eat. Intravenous injections failed either to decrease the steady-state pressure of the eye or to modify the intraocular dynamics. In the rabbit and cat, close arterial perfusions of 1 to 10 x 10^-6 M ouabain were without effect on the intraocular dynamics. Similar negative effects on intraocular dynamics were observed following direct perfusions of a 10^-5 M solution of ouabain into the posterior chamber of the rabbit eye for a period of 30 minutes. Direct injections of 1 to 100 µg ouabain into the vitreous body caused, after 24 hours, a significant increase in the outflow facility and protein content of aqueous humor. The significance of these findings to the possible role of the cardiac glycoside sensitive Na, K ion dependent ATPase in the secretion of aqueous humor is discussed.