Figure 6. Extra-lenticular changes in Cys-Gly and cystinyl-bis-glycine levels during lens culture. Bovine lenses were incubated in 40 ml of standard medium containing 0.5 mM Cys-Gly alone (squares) or in the presence of 10 µM bestatin (circles); reduced and disulfide forms of the thiol (open and closed symbols, respectively) were measured and reported as % equivalents of the initial CysGly concentration. Diamonds refer to lens incubation performed in standard medium supplemented with 0.25 mM cystinyl-bis-glycine; the concentration of the disulfide in this incubation is reported as % of the initial value. Values are reported as the mean of at least three different experiments; the error bars represent the standard error of the mean.