AIM To examine the projection of protein kinase Cγ isoform (PKCγ) immunoreactive neurons from the medullary and spinal dorsal horns to the solitary tract nucleus in the rat. METHODS Fluoro gold (FG) retrograde tracing combined with immunofluorescence histochemical staining for PKCγ was used. RESULTS PKCγ immunoreactive neurons were observed in laminae Ⅰ, Ⅱ, Ⅲ of the medullary and spinal dorsal horns and lateral spinal nucleus. After injecting FG into the solitary tract nucleus, FG retrogradely labeled...