大鼠纹状体边缘区内5-HT_(2A)受体的分布──原位杂交和免疫组织化学研究

已知纹状体边缘区有密集的 5 -HT纤维及终末分布。为了观察 5 -HT2 A受体 m RNA是否在大鼠纹状体边缘区表达 ,从基因分子水平和细胞水平进一步证明大鼠纹状体边缘区能否合成 5 -HT2 A受体 ,用地高辛标记的寡核苷酸探针进行原位杂交 ,研究了大鼠纹状体边缘区的 5 -HT2 A受体 m RNA的表达及分布。原位杂交结果发现 5 -HT2 A受体 m RNA阳性杂交信号在纹状体的分布不均匀 ,尾壳核只有少量中等大小的阳性胞体 ,苍白球也只有少量较大的阳性胞体 ,而在尾壳核和苍白球之间的边缘区部位则可见到许多中等大小的梭形阳性神经元胞体 ,并呈现密集的带状分布。免疫组织化学结果观察到 5 -HT受体阳性神经元胞体在纹状体的分布与原位杂交结果一致。本实验结果推测 ,大鼠纹状体边缘区神经元可以合成 5 -HT2 A受体 ,具有接受和整合 5 -HT神经递质的功能

DISTRIBUTION OF 5-HT2A RECEPTOR IN MARGINAL DIVISION OF RAT STRIATUM -- AN in situ HYBRIDIZATION AND IMMUNOHISTOCHEMICAL STUDY

s The in situ hybridization and immunohistochemistry method were used to observe the expression of 5 HT 2A receptor mRNA in the marginal division of rat striatum and to identify whether marginal division can synthesize 5 HT 2A receptor at gene level and cell level in the present study. Positive 5 HT 2A receptor mRNA hybridized signals were distributed unevenly in the striatum. There were few positive neurons in the caudate putamen and globus pallidus. However, numerous medium sized 5 HT 2A receptor positive fusiform neurons were found in the marginal division at the caudomedial border of the rat striatum. The positive neurons were densely packed in a dorsoventrally arranged band within the marginal division. The distribution of immunohistochemical reactivities in the rat striatum is similar to the results of in situ hybridization. The present study suggested that the 5 HT 2A receptor can be synthesized in the marginal division of rat striatum, and the marginal division may be involved the function of receiving and integration of 5 HT. (Figures 1～6 on plate 5)