It is shown here that hedgehog proteins possess novel activities beyond phenotype specification. Using cultures derived from the embryonic day 14.5 (E14.5) rat ventral mesencephalon, we show that hedgehog is also trophic for dopaminergic neurons. Interestingly, hedgehog not only promotes dopaminergic neuron survival, but also promotes the survival of midbrain GABA-immunoreactive (GABA-ir) neurons.