FIGURE 5.

Cx46 is essential for the maintenance of adequate levels of GSH in the lens nucleus. A and B, amount of GSH normalized to wet weight in the cortical (A) and nuclear (B) fraction of lenses obtained from wild type (WT), Cx46 knock-out (Cx46KO), and Cx50 knock-out (Cx50KO) are shown. In WT lenses, GSH levels were high in the cortical fraction but much lower in the nucleus. The absence of Cx46 or Cx50 did not significantly affect GSH levels in the cortex. In comparison, knock-out of Cx46 but not Cx50 caused a robust reduction in GSH levels in the nuclear fraction. Values represent means ± S.E. from five lenses each obtained from wild type, Cx46 KO, and Cx50 KO mice. C, decrease in GSH in C, 4, and 6 months (mo) of age. Substantial reductions in GSH levels were found in the nuclear fraction but not the cortical fraction of Cx46 KO lenses at all developmental time points. N values are given in the text.