V. Fontaine et al., CHANGES IN GANGLIOSIDE COMPOSITION OF PHOTORECEPTORS DURING POSTNATALMATURATION OF THE RAT RETINA, Glycobiology, 8(2), 1998, pp. 183-190
To examine at which stage the unusual ganglioside composition observed
in adult retinal photoreceptor cells was established, and to see whet
her ganglioside changes could be correlated to distinct maturational e
vents, quantitative and qualitative variations in gangliosides within
pure sheets of photoreceptors during postnatal differentiation and agi
ng of retina were studied. Retinas were separated into their component
layers, (particularly photoreceptor layers uncontaminated by other ne
uronal types) by exploiting a technique of mechanical separation by vi
bratome. We extracted lipids from the cell membranes and analyzed the
ganglioside composition by high performance thin layer chromatography.
The data show that from the earliest recordable postnatal age (6 days
) until late in life (18 months), photoreceptors contain low quantitie
s of lipid-bound N-acetyl neuraminic acid and a simplified ganglioside
profile compared to inner retinal neurons, Specific ganglioside chang
es occur within photoreceptor cells during postnatal maturation and ag
ing, with downregulation of a-pathway GM1 and overlapping upregulation
of b-pathway GD1b taking place during the period corresponding to out
er segment formation, correlating with the onset of retinal function.