Immunohistochemical localization of raf protein kinase in dendritic spines and spine apparatuses of the rat cerebral cortex.

The ultrastructural localization of raf protein (product of the raf protooncogene) in the neocortex, pyriform cortex and hippocampus of the rat has been investigated by means of pre-embedding immunohistochemistry. Specificity of the antiserum was tested with Western blotting. Besides the immunoreactivity of the dendrites, remarkably strong immunostaining of the dendritic spines and spine apparatuses was noted in each of the investigated areas. The postsynaptic densities were also stained. Since raf proteins are serine/threonine-specific protein kinases, our findings could be important steps toward the understanding of dendritic spine plasticity.