Synaptic loss reflected by secretoneurin-like immunoreactivity in the human hippocampus in Alzheimer's disease

Eur J Neurosci. 1998 Mar;10(3):1084-94. doi: 10.1046/j.1460-9568.1998.00121.x.


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.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Alzheimer Disease / metabolism*
  • Alzheimer Disease / pathology*
  • Calbindin 2
  • Entorhinal Cortex / metabolism
  • Entorhinal Cortex / pathology
  • Female
  • Hippocampus / metabolism*
  • Hippocampus / pathology*
  • Humans
  • Immunohistochemistry
  • Male
  • Nerve Tissue Proteins / metabolism
  • Neuropeptides / metabolism*
  • Paraffin Embedding
  • S100 Calcium Binding Protein G / metabolism
  • Secretogranin II
  • Synapses / pathology*


  • CALB2 protein, human
  • Calbindin 2
  • Nerve Tissue Proteins
  • Neuropeptides
  • S100 Calcium Binding Protein G
  • Secretogranin II
  • secretoneurin