Differentiation of cones in cultured rabbit retina: effects of retinal pigment epithelial cell-conditioned medium.

This study was aimed at investigating the postnatal differentiation of cone photoreceptors in the rabbit retina in an organotypic explant culture system. Both short wavelength (S) and middle wavelength (M) cone opsins were expressed in culture but M cones appeared only in retinal explants from the dorsal half of the eye. Stimulating the explants with retinal pigment epithelial cell (RPE) conditioned medium resulted in a suppression of opsin expression despite of an increase of the number of presumptive peanut agglutinin-labeled cones.