Substance P-positive thalamocaudate neurons in the center median-parafascicular complex in the cat

Substance P-like immunoreactivity was found immunohistochemically in some neurons in the center median-parafascicular complex (CM-Pf) of the thalamus in the cat. Some of these substance P-positive CM-Pf neurons were also labeled retrogradely with horseradish peroxidase which was injected into the caudate nucleus.