Noninvasive multiphoton fluorescence microscopy resolves retinol and retinal condensation products in mouse eyes.

ABSTRACT: Multiphoton excitation fluorescence microscopy (MPM) can image certain molecular processes in vivo. In the eye, fluorescent retinyl esters in subcellular structures called retinosomes mediate regeneration of the visual chromophore, 11-cis-retinal, by the visual cycle. But harmful fluorescent condensation products of retinoids also occur in the retina. We report that in wild-type mice, excitation with a wavelength of ?730 nm identified retinosomes in the retinal pigment epithelium, and excitation with a wavelength of ?910 nm revealed at least one additional retinal fluorophore. The latter fluorescence was absent in eyes of genetically modified mice lacking a functional visual cycle, but accentuated in eyes of older wild-type mice and mice with defective clearance of all-trans-retinal, an intermediate in the visual cycle. MPM, a noninvasive imaging modality that facilitates concurrent monitoring of retinosomes along with potentially harmful products in aging eyes, has the potential to detect early molecular changes due to age-related macular degeneration and other defects in retinoid metabolism.

SUBMITTER: Palczewska G 

PROVIDER: S-EPMC3057900 | biostudies-literature | 2010 Dec

REPOSITORIES: biostudies-literature