摘要
为探讨铝对学习记忆功能的影响及机制，３０只大鼠分别用基础饲料和添加铝的饲料喂养１２个月后，记录给予高频刺激前后诱发的大鼠海马ＣＡ３区群体峰电位（Ｐｓ）幅度变化。结果：基础饲料组在高频刺激后ＰＳ幅度加大，即引起了突触传递的长时程增强（ＬＴＰ）；低铝组和高铝组高频刺激前ＰＳ幅度分别为基础饲料组［（４４９．６±９２．５）μＶ］的５１．４％和２５．２％（均为Ｐ＜０．０５），但高频刺激仍可使低铝组产生ＬＴＰ，而高铝组未出现ＬＴＰ。ＣＡ３区微量注射ＮＯ清除剂血红蛋白（Ｈｂ）后基础组和低铝组ＰＳ幅度分别减至注射Ｈｂ前的（３４．７±１０．９）％和（２６．１±１２．９）％，高铝组无明显改变。结果提示铝可降低ＣＡ３区ＰＳ幅度和阻止ＬＴＰ形成，此作用与铝剂量有关，ＮＯ途径也可能参与铝的作用。
Thirty Wistar rats were divided into four groups:group A was given standard rat food, group B received diet containing citrate,group C and D received diet containing Al 500 mg/kg and 2 500 mg/kg respectively,for twelve months. Following a brief train stimulation of high-frequency in the perforant path,the change of population spike(PS)recorded in the hippocampal CA3 region was observed.The results were as follows:1.In group A, the amplitude of PS elicited by single test stimulation was increased with the elevation of test stimulative strength.After receiving train stimuli,the PS amplitudes caused by 20 V,30 V,40 V and 50 V test stimulation all were higher than control levels, e. i.LTP was produced. The results of group B were similar to those of group A, suggesting that the formation of LTP was not affected by citrate.2.In groups C and D,the amplitudes of PS elicited by 30V were lower than that of group A,the PS of group C and D were 51.4% and 25.2% of that of group A [(449.6±92.5)μV]respectivily (P<0.05),but the difference of PS between group C and D was not statistically significant. However, following being given train stimuli, PS of group C still was strengthened; while group D did not alter PS level,e. i. train stimulation failed to induce LTP.3.We also observed that the amplitudes of PS in groups A and C both were decreased after Hb was microinjected into CA3 region, being (34.7±19.0)%and(26.1±12.9)%before Hb respectivily;but in group D PS was nearly unaffected. These results indicate that the amplitude of PS might be attenuated significantly by aluminum ,in the rats receiving high dose of Al LTP even cannot be induced. The NO might be involved in the above-mentioned role of Al.The exact mechanism of PS being affected by Al awaits further investigation.
出处
《同济医科大学学报》
CSCD
北大核心
1996年第5期350-353,共4页
Acta Universitatis Medicinae Tongji
基金
国家自然科学基金
