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Neurotransmitters, peptides, and neural cell adhesion molecules in the cortices of normal elderly humans and Alzheimer patients: a comparison
Yew DT, Li WP, Webb SE, Lai HW, Zhang L.. Experimental gerontology, 1999-01-01
Topic: Amyloid, tau and blood-test diagnosis
Immunocytochemical techniques was used to compare the proportion of neurons expressing various neurotransmitters (tyrosine hydroxylase, choline acetyltransferase and gamma-aminobutyric acid), neuropeptides (Leu-enkephalin and substance P) and neural cell adhesion molecules (NCAM) in the hippocampus, frontal (area 10) and occipital (area 17) cortices of neurologically normal elderly humans to that of age-matched Alzheimer disease (AD) patients. There was no difference in the proportion of GABAergic and cholinergic cells between the normal and AD groups in all three brain regions studied. However, the catecholaminergic cells in the frontal cortex of the AD patients revealed a significant decrease. The catecholaminergic cells present in the cortex were both neurons and astrocytes, as revealed by a double immunostaining of tyrosine hydroxylase and glial fibrillary acid protein (GFAP). Furthermore, the difference in the proportion of cells expressing Substance P and Leu-enkephalin was minimal between the two groups studied. Although there was little difference in the levels of NCAM in the occipital cortex and hippocampus of the two groups, there were significantly fewer positive NCAM neurons in the frontal cortex of AD than normal aging individuals.
Key findings
- However, the catecholaminergic cells in the frontal cortex of the AD patients revealed a significant decrease.
- The catecholaminergic cells present in the cortex were both neurons and astrocytes, as revealed by a double immunostaining of tyrosine hydroxylase and glial fibrillary acid protein (GFAP).
- Although there was little difference in the levels of NCAM in the occipital cortex and hippocampus of the two groups, there were significantly fewer positive NCAM neurons in the frontal cortex of AD than normal aging individuals.
Why it matters
Comparing brain tissue from normal elderly people and Alzheimer's patients, this study found no difference in GABAergic and cholinergic cells, but a significant decrease in catecholaminergic cells and NCAM-positive neurons in the frontal cortex of Alzheimer's patients. This is a tissue comparison describing brain changes, not a test of any treatment, cure or prevention.
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Study details
- Evidence strengthLow
How this study scored 32/100
Published in a peer-reviewed journal. Scored zero for study design, sample size, effect reported, studied in people and randomised / blinded because the record does not state it. We have no data on senior author's track record, so that was left out: it earned 31 of the 96 points we could judge it on, which is 32 out of 100.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (Experimental gerontology) |
| Journal's citation record | 2 / 4 | Experimental Gerontology: journal h-index 195 (OpenAlex, 2026-10-29) |
| Study design | 0 / 12 | No study design recorded — scores zero, not guessed (not stated in the record — scored 0) |
| Strength of evidence | 1 / 5 | Rated “low” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 1 / 5 | 1999 — older than 20 years, still counted |
| Sample size | 0 / 4 | Participant count not stated — scores zero (not stated in the record — scored 0) |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 0 / 3 | Not stated whether this was studied in people — scores zero (not stated in the record — scored 0) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | 4 / 7 | Cited 43 times (OpenAlex, 2026-10-10) |
| Citations per year | 1 / 5 | 1.5 citations a year over 29 year(s) since 1999 |
| Impact for its field and year | 2 / 6 | Cited 1.0× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 0 / 6 | No other study in this library cites it |
| Still being cited | 0 / 4 | Cited 1 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | — / 4 | OpenAlex's profile for last-listed author L Zhang holds only 3 work(s), too few to judge a track record — left out of this score |
| Institution's track record | 1 / 3 | Chinese University of Hong Kong: institution h-index 1,100 (OpenAlex) |
| Multi-centre collaboration | 0 / 3 | OpenAlex lists 1 institution(s) in 1 country — scores zero (affiliation lists can be incomplete) |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 10197733) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Points | 31 / 96 | Scored on 19 of 20 parts. We have no data for the rest, so they are left out: 31 of the 96 points we could judge it on is 32 out of 100. |
| Total | 32 / 100 | — |
What each of these 20 components measures, and what this score is not →
Read the original
May need a subscription Unpaywall, Europe PMC and OpenAlex found no free copy of the full text (checked 10 Oct 2026), so the publisher may charge for it. The PubMed abstract is free.
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. Check the citation against the original before you use it.
APA 7th
Yew, D. T., Li, W. P., Webb, S. E., Lai, H. W., & Zhang, L. (1999). Neurotransmitters, peptides, and neural cell adhesion molecules in the cortices of normal elderly humans and Alzheimer patients: a comparison. Experimental gerontology. https://doi.org/10.1016/s0531-5565(98)00017-5
Vancouver
Yew DT, Li WP, Webb SE, Lai HW, Zhang L. Neurotransmitters, peptides, and neural cell adhesion molecules in the cortices of normal elderly humans and Alzheimer patients: a comparison. Experimental gerontology. 1999. doi:10.1016/s0531-5565(98)00017-5. PMID: 10197733.
BibTeX
@article{yew1999-10197733,
author = {Yew, D. T. and Li, W. P. and Webb, S. E. and Lai, H. W. and Zhang, L.},
title = {{Neurotransmitters, peptides, and neural cell adhesion molecules in the cortices of normal elderly humans and Alzheimer patients: a comparison}},
journal = {Experimental gerontology},
year = {1999},
doi = {10.1016/s0531-5565(98)00017-5},
pmid = {10197733},
url = {https://doi.org/10.1016/s0531-5565(98)00017-5}
}
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