Factors Affecting the Rate of Lactate Production in Rat Lens

Abstract

The rate of lactate production from various glycolytic intermediates was tested with a dispersed lens incubating system. Conditions required to establish maximal linear activity (lactate production vs. time) in each case were examined. It was confirmed that under noninhibitory concentrations of ATP, hexokinase paced glycolysis. At pH 7.05 the glycolytic rate was 40% of that at pH 7.43 (37.5.degree. C); pH variations affected early but not late steps of glycolytic sequence. In agins lenses the glycolytic rate (based on lens wet weight) was reduced to 52% of young lenses; phosphofructokinase in old lenses seemed to have partially lost its capacity to phosphorylate fructose-6-phosphate.