title: Synaptic loss reflected by secretoneurin-like immunoreactivity in the human hippocampus in Alzheimer's disease.
abstract: Secretoneurin is a recently described peptide derived by endoproteolytic processing from secretogranin II, previously named chromogranin C. In this study, we have investigated the distribution of secretoneurin-like immunoreactivity in the human hippocampus in controls and in Alzheimer's disease patients, and compared the staining pattern to that of calretinin. Secretoneurin-like immunoreactivity is present throughout the hippocampal formation. At the border of the dentate molecular layer and the granule cell layer, a band of dense secretoneurin immunostaining appeared. In this part, as in the area of the CA2 sector, the high density of secretoneurin-immunoreactivity coincided with calretinin-like immunoreactivity. The mossy fibre system displayed a moderate density of secretoneurin-immunoreactivity. In the entorhinal cortex, a particularly high density of secretoneurin-immunoreactivity was observed. The density of secretoneurin-like immunoreactivity was significantly reduced in the innermost part of the molecular layer and in the outer molecular layer of the dentate gyrus in Alzheimer's disease. For calretinin-like immunoreactivity, a less pronounced decrease was found in the innermost part of the molecular layer. About 40-60% of neuritic plaques were secretoneurin-immunopositive. This study shows that secretoneurin is distinctly distributed in the human hippocampus and that significant changes of secretoneurin-like immunoreactivity occur in Alzheimer's disease, reflecting synaptic loss.
authors.affiliation: Clinic of Psychiatry, Innsbruck, Austria.
authors.forename: W A
authors.initials: WA
authors.lastname: Kaufmann
authors.forename: U
authors.initials: U
authors.lastname: Barnas
authors.forename: C
authors.initials: C
authors.lastname: Humpel
authors.forename: K
authors.initials: K
authors.lastname: Nowakowski
authors.forename: C
authors.initials: C
authors.lastname: DeCol
authors.forename: P
authors.initials: P
authors.lastname: Gurka
authors.forename: G
authors.initials: G
authors.lastname: Ransmayr
authors.forename: H
authors.initials: H
authors.lastname: Hinterhuber
authors.forename: H
authors.initials: H
authors.lastname: Winkler
authors.forename: J
authors.initials: J
authors.lastname: Marksteiner
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000378:metabolism* / Q000473:pathology*; D064032:Calbindin 2; D018728:Entorhinal Cortex / Q000378:metabolism / Q000473:pathology; D005260:Female; D006624:Hippocampus / Q000378:metabolism* / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009479:Neuropeptides / Q000378:metabolism*; D016612:Paraffin Embedding; D064030:S100 Calcium Binding Protein G / Q000378:metabolism; D053381:Secretogranin II; D013569:Synapses / Q000473:pathology*
chemical_list: C576764:CALB2 protein, human; D064032:Calbindin 2; D009419:Nerve Tissue Proteins; D009479:Neuropeptides; D064030:S100 Calcium Binding Protein G; D053381:Secretogranin II; C081159:secretoneurin