Abstract
Abstract: :
Purpose: To determine the immunolocalization of CNTFRα in the retina of several mammalian species including: mouse, rat, cat, dog, sheep, pig, horse, and human. Methods: Paraformaldehyde fixed retinas (Human: 2 % PAF for over 1 year; other species: 4 % PAF for 3 hours followed by 2 % PAF for 24 hours) were cryoprotected in gradient sucrose concentrations, embedded in OCT and sectioned. Three polyclonal antibodies directed against chick, rat or human CNTFRα were used. The anti-rat (sc-1914) and anti-human (sc-1913) CNTFRα antibodies were available commercially; the anti-chick antibody was made by one of the authors (H.R.). Results: By immunofluorescence the anti-rat and human CNTFRα antibodies labeled exclusively the photoreceptor inner (IS) and outer (OS) segments in all species but human (no label) and mouse. In mouse CNTFRα and PNA label co-localized, suggesting that expression was limited to cones. A similar pattern of staining of the IS and OS was observed using an immunoenzymatic method (ABC kit). The anti-chick CNTFRα antibody labeled (ABC method) the photoreceptor IS in all species except mouse and rat. Labeling of the cone perinuclear region, axon and synaptic terminal was observed in the dog, pig and human, and immunoreactivity of the INL, IPL, GCL and NFL was present in all species. Conclusions: Although photoreceptor IS were labeled with all three CNTFRα antibodies in most species, we observed a variation in the labeling of the inner retina. Further studies are needed to address the specificity of these antibodies in order to evaluate the expression of CNTFRα in the retina, particularly in the photoreceptor cells.
Keywords: receptors: pharmacology/physiology • retina • immunohistochemistry