McQuiston A R, Madison D V
Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, California 94305, USA.
J Neurosci. 1999 Apr 15;19(8):2887-96. doi: 10.1523/JNEUROSCI.19-08-02887.1999.
We examined the function of nicotinic acetylcholine receptors (nAChRs) in interneurons of area CA1 of the rat hippocampus. CA1 interneurons could be classified into three categories based on nicotinic responses. The first class was depolarized by alpha7 nAChRs, found in all layers of CA1 and as a group, had axonal projections to all neuropil layers of CA1. The second class had both fast alpha7 and slow non-alpha7 nAChR depolarizing responses, was localized primarily to the stratum oriens, and had axonal projections to the stratum lacunosum-moleculare. The third group had no nicotinic response. This group was found in or near the stratum pyramidale and had axonal projections almost exclusively within and around this layer. Low concentrations (500 nM) of nicotine desensitized fast and slow nAChR responses. These findings demonstrate that there are distinct subsets of interneurons with regard to nicotinic receptor expression and with predictable morphological properties that suggest potential cellular actions for nicotinic receptor activation in normal CNS function and during nicotine abuse.
我们研究了大鼠海马体CA1区中间神经元中烟碱型乙酰胆碱受体（nAChRs）的功能。基于烟碱反应，CA1中间神经元可分为三类。第一类被α7 nAChRs去极化，在CA1的所有层均有发现，并且作为一个群体，其轴突投射至CA1的所有神经毡层。第二类同时具有快速α7和慢速非α7 nAChR去极化反应，主要定位于海马下托，其轴突投射至分子层。第三组没有烟碱反应。该组位于锥体层或其附近，其轴突几乎仅投射至该层及其周围。低浓度（500 nM）的尼古丁使快速和慢速nAChR反应脱敏。这些发现表明，在烟碱受体表达方面，存在不同的中间神经元亚群，且具有可预测的形态学特性，这表明烟碱受体激活在正常中枢神经系统功能以及尼古丁滥用过程中可能具有潜在的细胞作用。
