Fowler K R, Olton D S
Brain Res. 1984 Oct 29;321(1):21-32. doi: 10.1016/0006-8993(84)90677-2.
This research examined the electrophysiological, behavioral and neuroanatomical changes following an injection of kainic acid (KA) which destroyed most of the CA3 pyramidal cells in the hippocampus. For 5 days following the injection of KA, the evoked potential (EP) in the CA1 pyramidal cells produced by stimulation of the perforant path (PP), dentate gyrus (DG), or remaining CA3 cells was markedly altered. These rats also had an impairment of choice accuracy in a discrimination task that required working memory. Within 30 days, however, all EPs had become more normal. Choice accuracy had either returned to criterion levels, or improved substantially above that immediately following the KA injection. Analysis of the EPs indicated that the normal trisynaptic pathway through the hippocampus had been re-established. Neuroanatomical examination of the remaining CA3 pyramidal cells showed a marked increase in cross-sectional area. These data provide an electrophysiological description of the effects of KA on neuronal transmission in the hippocampus, and suggest that the behavioral recovery following these injections was due to sprouting of the remaining CA3 cells which re-established the trisynaptic pathway in the hippocampus.
本研究检测了注射海藻酸（KA）后所产生的电生理、行为及神经解剖学变化，注射KA破坏了海马体中大部分CA3锥体细胞。在注射KA后的5天里，由刺激穿通通路（PP）、齿状回（DG）或剩余CA3细胞所诱发的CA1锥体细胞中的诱发电位（EP）发生了显著改变。这些大鼠在一项需要工作记忆的辨别任务中，选择准确性也出现了损伤。然而，在30天内，所有的诱发电位都变得更加正常。选择准确性要么恢复到标准水平，要么大幅提高到高于KA注射后立即达到的水平。对诱发电位的分析表明，通过海马体的正常三突触通路已经重新建立。对剩余CA3锥体细胞的神经解剖学检查显示，其横截面积显著增加。这些数据提供了KA对海马体神经元传递影响的电生理描述，并表明这些注射后的行为恢复是由于剩余CA3细胞的发芽，重新建立了海马体中的三突触通路。
