Chromogranin A in the central nervous system of the rat: pan-neuronal expression of its mRNA and selective expression of the protein.
Chromogranin A, a glycoprotein stored in secretory granules of neuroendocrine cells, displays a widespread distribution throughout the central nervous system of a variety of species. In situ hybridization histochemistry was employed to investigate the localization of chromogranin A mRNA in the central nervous system of the rat. The previously characterized monoclonal antibody, LK2H-10, was employed in an immunohistochemical study to compare the topographic localization of the chromogranin A protein with that of its mRNA. Although the latter, as revealed by in situ hybridization, displayed a ubiquitous, pan-neuronal localization throughout the rat brain, LK2H-10 immunoreactive cell bodies and axon terminals were disposed in a widespread, but highly regionally differential, distribution. This discrepancy suggests that chromogranin A is processed in a regionally differential fashion in the rat brain to yield one or multiple variant forms, one of which is specifically recognized by LK2H-10. Catecholaminergic cell groups consistently displayed LK2H-10 immunoreactivity. LK2H-10 immunopositive axon terminals were prominent in the circumventricular organs. In addition, LK2H-10 immunoreactivity was also detected in a subset of astrocytes which demonstrated a widespread, but anatomically restricted, pattern of distribution. Consequently, the variant of chromogranin A labelled by LK2H-10 represents a novel neurochemical marker for regionally differential astrocytic diversity.
Woulfe
J
J
Department of Pathology, McMaster University Hamilton Health Sciences Corporation, Hamilton, Ontario, Canada. woulfej@hamcivhos.on.ca
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Munoz
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D000818:Animals; D000911:Antibodies, Monoclonal; D014408:Biomarkers, Tumor / Q000032:analysis* / Q000235:genetics* / Q000276:immunology; D015153:Blotting, Western; D001923:Brain Chemistry / Q000235:genetics*; D001933:Brain Stem / Q000737:chemistry; D002531:Cerebellum / Q000737:chemistry; D053379:Chromogranin A; D002864:Chromogranins / Q000032:analysis* / Q000235:genetics* / Q000276:immunology; D004805:Ependyma / Q000737:chemistry; D005455:Fluorescent Antibody Technique; D015972:Gene Expression Regulation, Neoplastic / Q000502:physiology; D017403:In Situ Hybridization; D008297:Male; D016548:Prosencephalon / Q000737:chemistry; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D013116:Spinal Cord / Q000737:chemistry*
D000911:Antibodies, Monoclonal; D014408:Biomarkers, Tumor; D053379:Chromogranin A; D002864:Chromogranins; D012333:RNA, Messenger; C506153:chromogranin A, rat