Developmental changes in the distribution of S-100 in avian neural retina

Localization of S-100 in cells of embryonic and mature chick neural retina was studied by immunostaining of tissue sections with antiserum to S-100 and indirect immunofluorescence. Immunostaining was found to be localized predominantly in the neurons. In embryonic retina, the intensity of immunostaining increased transiently in each class of neurons at the time when they were undergoing organization within their stratum. Late embryonic and mature retina reacted weakly with the antiserum, with the exception of certain 'giant' ganglion cells that immunostained intensely. Müller cells, the only kind of glia cells in the chicken transiently in each class of neurons at the time when they were undergoing organization within their stratum. Late embryonic and mature retina reacted weakly with the antiserum, with the exception of certain 'giant' ganglion cells that immunostained intensely. Müller cells, the only kind of glia cells in the chicken transiently in each class of neurons at the time when they were undergoing organization within their stratum. Late embryonic and mature retina reacted weakly with the antiserum, with the exception of certain 'giant' ganglion cells that immunostained intensely. Müller cells, the only kind of glia cells in the chicken retina, did not react prominently with the antiserum at any of the stages examined and could not be discerned by immunostaining either in embryonic or in mature retina. The results indicate that in chick neural retina S-100 is found predominantly in neurons, and it increases and declines in different subpopulations of neurons coordinately with changes in the development and maturation if this tissue.