The immunohistochemical staining for the neuron-specific HuC/HuD protein showed an increase of around 35% (p < 0.05) in myenteric plexus neurons in the ileum of animals with Parkinsonism that suffered damage caused by the nigrostrial injection of the neurotoxin 6-OHDA (Figure 7a–c). This evidence concerns the gene ELAVL4 and Parkinson disease.