Abstract |
As Ginkgo has been shown to improve age-related memory de fi cits and beta-amyloid-related peptides have been suggested to play a signi fi cant role in memory degeneration in Alzheimer's disease, the present study was carried out to examine the effect of two major ginkgolides, A and B, on beta-amyloid peptide-modulated acetylcholine (ACh) release from hippocampal brain slices. Addition of beta-amyloid fragment(25-35) (0.01-1 micro M) in the superfusion medium suppressed the K(+)-evoked [(3)H]-ACh release from the rat hippocampal slices in a concentration-related manner; a 40% reduction in ACh out fl ow was observed with the highest amyloid concentration used (1 micro M). Inclusion of ginkgolide B (GKB, 0.01-10 micro M) caused a concentration-related reversion of the inhibitory effect elicited by the effective concentration of beta-amyloid (1 micro M). The reversal of the beta-amyloid-inhibited ACh release by GKB (1 micro M) was not blocked by tetrodotoxin (1 micro M) indicating a direct interaction of GKB on the cholinergic nerve terminals. In contrast, addition of the same concentration range of ginkgolide A (GKA, 0.01-10 micro M) had no effect on beta-amyloid-inhibited ACh release. These results suggest that GKB may elicit its anti-amnesic effect by minimizing the inhibitory effect of beta-amyloid peptides on cholinergic transmission.
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Authors | Tze-Fun Lee, Chieh-Fu Chen, Lawrence C H Wang |
Journal | Phytotherapy research : PTR
(Phytother Res)
Vol. 18
Issue 7
Pg. 556-60
(Jul 2004)
ISSN: 0951-418X [Print] England |
PMID | 15305316
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Amyloid beta-Peptides
- Diterpenes
- Ginkgolides
- Lactones
- Plant Extracts
- ginkgolide B
- Acetylcholine
- ginkgolide A
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Topics |
- Acetylcholine
(metabolism)
- Alzheimer Disease
(prevention & control)
- Amyloid beta-Peptides
(drug effects, metabolism)
- Animals
- Diterpenes
(administration & dosage, pharmacology, therapeutic use)
- Dose-Response Relationship, Drug
- Ginkgo biloba
- Ginkgolides
- Hippocampus
(drug effects)
- Lactones
(administration & dosage, pharmacology, therapeutic use)
- Male
- Phytotherapy
- Plant Extracts
(administration & dosage, pharmacology, therapeutic use)
- Rats
- Rats, Sprague-Dawley
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