Loss of brainstem serotonin- and substance P-containing neurons in Parkinson's disease

G.M. Halliday

Abstract

Using postmortem immunohistochemical analysis, we have identified degeneration of several different neuronal cell groups in the brainstem of patients dying with idiopathic Parkinson's disease.

We report the first chemically identified loss of presumed serotonin neurons in the median raphe nucleus of the pons and of substance P-containing preganglionic neurons in the dorsal motor vagal nucleus.

This evidence is concordant with other evidence that the primary neuropathological process is not confined either to a single pathway or to neurons containing a particular transmitter. Rather it appears that Parkinson's disease affects several clases of neurons in localized areas of the brainstem.

http://www.sciencedirect.com/science...4e988e9b565366

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"Specific lower brainstem nuclei are consistently and strikingly affected in PD, with the Lewy body pathology primarily confined to noncatecholaminergic neurons. Lewy body degeneration of the dorsal vagal nucleus affects noncatecholaminergic large motor neurons but spares melanized cells.[43-45] Substance P-containing neurons within the dorsal vagal nucleus are most depleted, with 77% neuronal loss[40][46]; in contrast, nearby tyrosine hydroxylase-immunoreactive neurons are almost spared (<5% reduction).[46] Others have also reported nearly complete sparing of catecholaminergic neurons within the medulla.[47][48] The noncatecholaminergic lateral medullary reticular nucleus is severely affected in PD,[49][50] with 85% loss of the substance P-containing neurons.[40]"

From:


http://www3.interscience.wiley.com/c...299/HTMLSTARTW

Glial-cell-line-derived neurotrophic factor (GDNF) enhances biosynthesis of substance P in striatal neurons in vitro

http://www.springerlink.com/content/dbhblrl3g3r1wecd/

A GOOD REVIEW ARTICLE ABOUT SUBSTANCE P:

http://medschool1.mc.vanderbilt.edu/...ncePReview.pdf