Cytochrome oxidase activity in retinas transplanted to the brainstem in rats.

Fetal retinas were transplanted to the brainstem of newborn rats and their morphological features were examined using the cytochrome oxidase histochemical method at maturity. The results showed that the inner segments of photoreceptors, outer and inner plexiform layers as well as ganglion cells with large somata were moderately to darkly stained for cytochrome oxidase. This pattern is basically the same as that observed in the normal retina, suggesting that cytochrome oxidase can be used not only for revealing spatial but also functional organization of retinal transplants.