Somatostatin in rat retina: localization by in situ hybridization histochemistry and immunocytochemistry

In order to analyse the mRNA-protein relationships of somatostatin containing neurons in the rat retina, we have used a combined method with in situ hybridization histochemistry using radio-labeled oligodeoxyribonucleotides complementary for rat somatostatin mRNA and immunocytochemistry using antiserum for somatostatin protein. We found double labeled amacrine cells in the innermost and outermost laminae of the inner nuclear layer as well as the displaced amacrine cells in the ganglion cell layer in the retina. Some cells in the inner nuclear layer had high levels of somatostatin mRNA. Radially immunostained interplexiform fibers were observed adjacent to the amacrine cells with high level of somatostatin mRNA. These data suggest the site of synthesis of somatostatin and post-translational migration of this neuropeptide within the rat retinal tissue.