Quantitative imaging of substance P in the human brain using a brain mapping analyzer

The distribution of substance P (SP)-like immunoreactive neurons in the bra ins of aged normal human was analyzed quantitatively. Consecutive coronal s ections in which the striatum and the substantia nigra were exposed widely, were obtained from the right hemisphere and stained immunohistochemically for SP. Each stained section was divided into approximately three million m icroareas and the immunohistochemical fluorescence intensity in each area w as measured using a human brain mapping analyzer, which is a microphotometr y system for analysis of the distribution of neurochemicals in a large tiss ue slice. These distributions are displayed in color and monochromatic grap hics. In the analyzed brain regions, conspicuously intense SP-like immunore activity was observed in the substantia nigra and the internal segment of t he globus pallidus. Within the substantia nigra, the SP-like immunoreactive intensity in the pars compacta was 25% higher than that in the pars reticu lata, and the distribution of melanin-containing neurons corresponded well to the distribution of the SP-containing structures. SP-like immunoreactive intensity in the internal segment of the globus pallidus, which was lower than that in the substantia nigra, was approximately twice as high as that in the external segment of the globus pallidus. Very intense immunoreactivi ty was localized at the most medial area of the internal segment of the glo bus pallidus. The SP-like immunoreactive intensity in the caudate nucleus a nd putamen was moderate, and the distribution was heterogeneous and observe d in patches. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.