In a previous study it was shown that the levels of NGF in the cerebrospinal fluid of patients affected by multiple sclerosis (MS) increase during the acute phase of the disease and decrease in the remission phase. In the present study, using an animal model of MS, we investigate whether any changes in NGF levels occur in brains of rats affected by Experimental Allergic Encephalomyelitis (EAE). The results show an enhanced level of NGF in the thalamus and spinal cord and a numerical increase of mast cells (MCs) expressing mRNA-NGF localized in these two regions. These observations suggest that NGF is involved in EAE and that MCs contribute to the local increase of NGF.