The effect of beta-amyloid on neurons and the influence of glucocorticoid and age on such effect

Abstract

To explore the relationship between β-amyloid (Aβ) and the pathogenesis of Alzheimer disease (AD), after injection of β-amyloid into the rat brain, the apoptosis of nerve cells and acetylcholine (Ach) content in rat hippocampus were examined by employing TUNEL technique and base hydroxylamine colorimetry respectively. The influence of age and glucocorticoid on the neurotoxic effect of Aβ was also analyzed. Aβ peptide could strongly induce the apoptosis of neurons in hippocampus, cortex and striate body (P<0.05 orP<0.01). In addition, the senility and glucocorticoid pre-treatment could enhance the toxic effect of Aβ(P<0.05 orP<0.01). It is concluded that Aβ may play an important role in the pathogenesis of Alzheimer disease via its induction of apoptosis of neurons and by decreasing the content of the Ach.

Keywords

Alzheimer disease / β-amyloid / glucocorticoid / acetylcholine

References

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