Aβ_((31-35))和ApoE_4对培养大鼠海马神经元的存活和生长的影响

EFFECTS OF APOE4 AND β-AMYLOID PROTEIN 31-35 ON SURVIVAL AND GROWTH OF THE NEURONS OF HIPPOCAMPUS IN CULTURE

为探讨β-淀粉样蛋白 ( Aβ)和载脂蛋白 E4( Apo E4)对培养大鼠海马神经元的作用 ,本文采用了神经细胞培养、MTT比色法、免疫组化及图象分析等技术进行了研究。结果显示 :( 1) MTT法测得 Aβ( 3 1 - 3 5) ( 10 μmol/ L) +Apo E4( 10 μg/ ml)和 Aβ( 3 1 - 3 5)( 2 0μmol/ L ) +Apo E4( 10μg/ ml)的 OD值 ,分别为 0 .197± 0 .0 2 1和 0 .191± 0 .0 2 4,明显低于对照组 ( 0 .2 2 9± 0 .0 3,P<0 .0 5 )。( 2 )这两组神经元胞体的最长径分别为 ( 10 .0 7± 1.98)μm和 ( 10 .0 1± 1.6 8)μm;最短径分别为 ( 6 .40± 0 .77)μm和 ( 6 .2 8± 0 .89) μm,明显低于对照组、Apo E4组、Aβ( 3 1 - 3 5) 组的最长径和最短径 ( P<0 .0 5 ) ;其突起平均长度分别为 ( 2 6 .36± 7.73) μm和 ( 2 3.86± 7.2 9)μm,明显低于对照组 ( 30 .88± 9.79)μm、Apo E4组 ( 30 .6 0± 7.30 )μm以及 Aβ( 3 1 - 3 5) ( 10μmol/ L )组 ( 2 8.34± 4.40 )μm( P<0 .0 5 )。 ( 3) Aβ( 3 1 - 3 5) ( 2 0 μmol/ L)组的突起平均长度为 ( 2 6 .81± 5 .42 ) μm,也明显低于对照组 ( 30 .88± 9.79) μm和Apo E4组 ( 30 .6 0± 7.30 )μm ( P<0 .0 5 )。本研究结果提示 ,Aβ( 3 1 - 3 5) +Apo E4对神经元的抑制作用较 Aβ(

The present study examined the neurotoxic effects of Aβ (31 35) and ApoE 4 on the neurons of hippocampus by using MTT assay and immunohistochemistry combined with morphometry measure in culture. (1) Forty eight hours after treatment, the results of MTT assay showed that average OD values of Aβ (31 35) (10 μmol/L)+ApoE 4(10 μg/ml) and Aβ (31 35) (20 μmol/L)+ApoE 4(10 μg/ml)are significantly decreased compared with that of the control group(P<0.05) in hippocampal neurons. (2) Four days after treatment, the average maximum and minimum diameters of neurons in group Aβ (31 35) (10 μmol/L)+ApoE 4(10 μg/ml) and Aβ (31 35) (20 μmol/L)+ApoE 4(10 μg/ml) were decreased significantly compared with those of control, group ApoE 4, group Aβ (31 35) (10 μmol/L) and Aβ (31 35) (20 μmol/L) (P<0.05); the average neurite length of group Aβ (31 35) (10 μmol/L)+ApoE 4(10 μg/ml) and Aβ (31 35) (20 μmol/L)+ApoE 4(10 μg/ml) were decreased significantly compared with those of control, group ApoE 4, group Aβ (31 35) (10 μmol/L)(P<0.05). (3) the average neurite length of group Aβ (31 35) (20 μmol/L) was decreased significantly over that of control, group ApoE 4(P<0.05). These results suggest that the neurotoxic effect of Aβ (31 35) +ApoE 4 is higher than that of Aβ (31 35) alone, which implies that ApoE 4 may cooperate with Aβ (31 35) in the aspect of neurotoxicity.