FIGURE 5.

Glutamine can support retinol formation in isolated mouse rod photoreceptors. Retinol and retinal were distinguished by exciting fluorescence with 340- and 380-nm light and collecting emission for >420 nm. IR, infrared images of the cells; fluorescence images of the cells before (Dark) and at different times after bleaching are shown with the same intensity scaling to facilitate comparisons. Glucose concentration was 5 mm; glutamine concentration was 0.2 mm. Experiments were performed at 37 °C.