Glycogen in retinal horizontal cells of the African mud catfish Clarias gariepinus (Burchell, 1822) and its physiological significance.

This paper reports on glycogen store in the retinal horizontal cells (HC) of the African mud catfish Clarias gariepinus, as seen by histochemical reaction with periodic acid Schiff (PAS) and transmission electron microscopy in light- as well as dark-adapted state. Glycogen is abundant in the large somata and less in their axons, characterised ultrastructurally by many microtubules and extensive gap junctions interconnecting them. There was no apparent difference in glycogen content in HC somata between light- and dark adaptation, but the axons clearly showed absence of glycogen in dark condition.

Aging of the human choriocapillaris: Evidence that early pericyte damage can trigger endothelial changes.

The choriocapillaris (CC), the capillary bed in the choroid, essentially nourishes the photoreceptor cells. Its damage in aging and age-related diseases significantly influences the survival of the photoreceptor cells. Earlier reports implicated endothelial loss in aged and diseased CC; however, age-related pericyte changes and their contribution in CC death remain unknown.

Localization of nitro-tyrosine immunoreactivity in human retina.

Oxidative stress (OS) is associated with retinal aging and age-related macular degeneration (AMD). In both cases there are reports for the presence of markers of lipid peroxidation in retinal cells. We investigated if nitrosative stress also occurs in the human retina with aging.