The effects of anoxia, glucose, ATP, and ouabain on Na, K, and Cl in the rabbit lens

Abstract

Rabbit lenses were incubated at 37 °C in Tyrode's solution which was aerated either with 95% O2 + 5% CO2 or with 95% N2 + 5% CO2. The Na, K, Cl, and water concentration in each lens was determined after the incubation period. A procedure was developed for oxidizing the sulfhydryl groups in the lens so that a semimicro, electrometric method for the determination of Cl could be used. The data showed that anoxia alone produced a decrease in K and an increase in Na and Cl. These electrolyte shifts were prevented by the addition of glucose (200 mg%) or ATP (10−3 M) to the bathing medium. When ouabain (10−6 M) was also added neither glucose nor ATP were effective in preventing the electrolyte changes induced by anoxia. These results permit three conclusions: (1) the electrolyte concentration of the lens can be supported by aerobic and anaerobic metabolism; (2) anaerobic metabolism of added glucose can prevent downhill movements of Na and K; and (3) exogenous ATP can also be utilized by the lens to prevent downhill movements of the cations.