Aβ5～35 and Apo E4 enhance neuronal intracellular free Ca2+
- VernacularTitle:β-淀粉样蛋白和载脂蛋白E4升高神经元胞内游离钙
- Author:
Yinghong TIAN
;
Zhibin YAO
;
Lihua ZHOU
;
Yao XIE
- Publication Type:Journal Article
- From:
Chinese Pharmacological Bulletin
2001;17(1):57-62
- CountryChina
- Language:Chinese
-
Abstract:
AIM To study the effects of Aβ25～35 and Apo E4 on neuronal intracellular free Ca2+(［Ca2+］i). METHODS Hippocampal and cortical neurons suspension of newborn(0～3 days) SD rats was produced. After incubated with fura-2/AM,the neurons suspension was divided into four groups: control, Aβ25～35, Apo E4, Aβ25～35+Apo E4. Each groups ［Ca2+］i was measured using a RF-5000 dual wavelength spectrofluorometer after incubated with double distilled water, Aβ25～35, Apo E4, Aβ25～35+Apo E4 for 3 min, respectively. The neurons outocorrelation function(ACF) of the scattering light intersity was analyzed by the microscope quasi-elastic light scattering(MQLS) technique The frequency shift line width by ACF. The Γ can sympolize the cell menbrane flilidity. RESULTS Both Aβ25～35 and Apo E4 could significantly enhance hippocampal and cortical neurons rest ［Ca2+］i, furthermore, the effect of 5 μmol*L-1 Aβ25～35 was higher than the effect of 1 μmol*L-1 Aβ25～35 (P<0.05), and they also amplified KCl-induced rise in ［Ca2+］i in hippocampal and cortical neurons(P<0.05). The interaction of Aβ25～35 and Apo E4 could also significantly enhance hippocampal and cortical neurons rest ［Ca2+］i andamplified KCl-induced rise in ［Ca2+］i in hippocampal and cortical neurons(P<0.05), but they had no synergic or additive effect.The frequency shift line widith Γ of both hippocampal and cortical neurons were decreased by both Aβ25-35 and ApoE4. CONCLUSION Aβ25～35 and Apo E4 could enhance neuronal intracellular free Ca2+, amd decrease meirpma; ,e,brame f;iodotu. But their interaction had no synergic or additive effect. It suggested that the amplified effect of Aβ25～35 and Apo E4 on neuronal ［Ca2+］i and membane fluidity may be relative to their neurotoxity.
