ULTRASTRUCTURAL STUDIES OF RETINAL, VISUAL CORTICAL (AREA 17), AND PARABIGEMINAL TERMINALS WITHIN THE SUPERIOR COLLICULUS OF GALAGO-CRASSICAUDATUS
ULTRASTRUCTURAL STUDIES OF RETINAL, VISUAL CORTICAL (AREA 17), AND PARABIGEMINAL TERMINALS WITHIN THE SUPERIOR COLLICULUS OF GALAGO-CRASSICAUDATUS
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DOI：
10.1002/cne.903190109
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发表时间：
1992-05-01
影响因子：
2.5
通讯作者：
HARTING, JK
中科院分区：
文献类型：
--
作者：
FEIG, S;VANLIESHOUT, DP;HARTING, JK
顺行标记的视网膜，视觉皮层（区17），和parabigeminal终端的形态和突触关系进行了分析内浅灰色（层griseum浅）的Galago crassicaudatus.Our数据retinocollicular投影显示两个群体的终端的大小。两种终末主要与树突棘形成突触，但也可与苍白囊泡填充（PVF）轮廓和树突轴形成突触。皮质顶盖终末含有圆形囊泡，主要与树突棘形成不对称突触;少数与PVF轮廓形成突触。我们的研究结果表明，有两个群体的皮质顶盖终末的基础上的差异在大小和形态的可能性。Parabigeminotectal配置文件包含密集包装的圆形小泡，使不对称的突触。这些终末在Galago只具有胆碱能，与不同大小的树突形成突触前连接。这种会聚发生在突触后膜上明显分离的区域。与此相反，视网膜终末和二叠层旁终末的会聚发生在突触后细胞的同一区域。
The morphology and synaptic relationships of anterogradely labeled retinal, visual cortical (area 17), and parabigeminal terminals have been analyzed within the superficial gray (stratum griseum superficiale) of Galago crassicaudatus.Our data regarding the retinocollicular projection reveal two populations of terminals based upon size. The population of smaller terminals are found in clusters, while the larger occur in isolation, Both populations of retinocollicular terminals form synapses primarily with dendritic spines, but synapses upon pale vesicle filled (PVF) profiles and dendritic shafts also occur.Corticotectal terminals contain round vesicles and make asymmetrical synapses, primarily onto dendritic spines; few form synapses with PVF profiles. Our findings suggest the possibility that there are two populations of corticotectal terminals based upon differences in size and morphology.Parabigeminotectal profiles contain densely packed round vesicles and make asymmetrical synapses. These terminals, which are exclusively cholinergic in Galago, are presynaptic to dendrites of various sizes.Convergence of retinal and cortical terminals has been observed. This convergence occurs on distinctly separate regions of the postsynaptic membrane. In contrast, convergence of retinal and parabigeminal terminals occurs on the same region of the postsynaptic cell(s).