The distribution of tachykinin NK₁ and NK₃ receptors in the prefrontal (Brodmann area 9) and visual cortex (Brodmann area 17) of formalin-fixed postmortem human brain tissue was studied by immunohistochemistry. NK₁-like immunoreactivity (NK₁-LI) was observed as a thin band at the cortical surface and dots of NK₁-LI localised on small non-pyramidal cells and in the neuropil (layers I–III). NK₃-LI was found in beaded fibres and cells with astrocyte-like morphology in the superficial cortical layers and white matter. Dots of NK₃-LI were prominent in the neuropil and on pyramidal (layers III/V) and non-pyramidal (layers V/VI) cells. The NK₃-LI was more abundant and widespread than the NK₁-LI. This is the first report of the distribution of the NK₁ receptor in the prefrontal and visual cortex of the human brain by immunohistochemistry.
Neuroscience Letters Vol. 283, Issue 3, p. 185-188