Bipolar cells in the turtle retina are strongly immunoreactive for glutamate.

Department of Cellular and Development Biology, Harvard University, Cambridge, MA 02138.
Proceedings of the National Academy of Sciences (Impact Factor: 9.81). 12/1988; 85(21):8321-5. DOI: 10.1073/pnas.85.21.8321
Source: PubMed

ABSTRACT Strong glutamate immunoreactivity was observed by both light and electron microscopy in bipolar cells of the turtle (Pseudemys scripta elegans) retina after postembedding immunohistochemistry. Virtually all bipolar cells showed strong labeling, on average 18 times that of the Müller (glial) cells. The data suggest that both on- and off-center bipolar cells are glutamatergic. Photoreceptors were also labeled, but with a labeling intensity about half that of the bipolar cells. Other types of retinal neurons showed less immunoreactivity, except for a small population of strongly labeled amacrine cells.

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