Glial fibrillary acidic protein and S-100 protein in pineal supportive cells: an electron microscopic study

Pineal supportive cells in a teleost were shown to contain the glial fibrillary acidic (GFA) and S-100 proteins by electron microscopic immunocytochemistry. Both proteins are known to exhibit a high degree of evolutionary conservation. The pineal photoreceptor cells did not stain for these marker proteins. A relationship between supportive cells and macroglial elements is therefore implied.