Melatonin is involved in a variety

No abstract

Many lines of evidence suggest that zinc may play an important neuromodulatory role in the central nervous system, including the retina. In this work, localization of zinc in the outer retina of carp was studied, using the silver amplification method, by light and electron microscopy. Reaction products (silver grains) were widely distributed throughout the retina, including photoreceptors, the outer and inner nuclear layers (ONL and INL), the ganglion cell layer (GCL), as well as in both outer and inner plexiform layers (OPL and IPL). Generally, staining for zinc was stronger in the outer retina than in the inner retina, and grains were aggregated with the greatest density in the OPL and the outer limiting membrane (OLM). Silver precipitates were also detected in the inner segments, axons, but not outer segments of photoreceptors. At the ultrastructural level, zinc was localized to myoid regions, mitochondria in the inner segments, internuclear space and nuclei of photoreceptors. In addition, silver grains were found in the terminals of photoreceptors, cone pedicles, and rod spherules, as well as in some processes in the OPL, which might be dendrites of horizontal cells. The presence of zinc in the terminals of photoreceptors suggests that zinc might be released from photoreceptor terminals and play modulatory roles in the outer retina.

Neural salient serine/arginine-rich protein 1 (NSSR1) expression has been found in mouse cerebral neurons, cerebellar Purkinje cells, pyramidal neurons and granule cells of dentate gyrus and regulates the pre-mRNA splicing of genes important for neural functions. In this study, we demonstrated that NSSR1 is expressed in rat retina and extensively distributed in the outer and inner plexiform layers. Double staining experiments showed that NSSR1 distributed mainly in ON-type bipolar cells and localized in the dendrites, somata and axon terminals. The result suggests that NSSR1 may play important roles in retinal function, possibly via regulating the neural-specific alternative splicing of genes.