Consistent with our previous results and the role of the PVN, the present study found that MS was associated with an increase in the expression of both the TLR4 protein and mRNA in the PVN of Tlr4+/+ mice, whereas levels of TLR4 and MyD88 expression in Tlr4-/- mice were significantly decreased. This evidence concerns the gene TLR4 and myeloid sarcoma.