Fusion of neuroblastoma cells with cells from normal retina yielded some cell lines that synthesize catecholamines and another that synthesizes acetylcholine. These results show that fusion of neuroblastoma cells with cells from the normal nervous system generates hybrid cells with new neural properties which have not been detected with the parental neuroblastoma cells. The new neural phenotypes are inherited and thus far have been perpetuated in a fairly stable fashion for more than 100 cell generations. This approach would appear to be a general one that can be used to obtain cell lines with other differentiated properties that can be used to elucidate reactions that are required for cell communication.