AFFERENT CONNECTIONS OF THE LATERAL AGRANULAR FIELD OF THE RAT MOTOR CORTEX
AFFERENT CONNECTIONS OF THE LATERAL AGRANULAR FIELD OF THE RAT MOTOR CORTEX
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DOI：
10.1002/cne.902170404
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发表时间：
1983-01-01
影响因子：
2.5
通讯作者：
PARHAM, C
中科院分区：
文献类型：
--
作者：
DONOGHUE, JP;PARHAM, C
应用逆行轴突运输技术研究了大鼠额叶皮质外侧无颗粒区（AG 1）的传入纤维联系。这种cytoarchitectonically不同的皮质领域形成了大部分的初级运动皮层（MI）的定义，皮质内微刺激研究。将辣根过氧化物酶（HRP）或与HRP结合的麦胚凝集素注射到AG 1中后，在前脑、丘脑和脑干中发现了逆行标记的细胞。在大脑皮层内，标记神经元主要存在于第一躯体感觉区（SI）、第二躯体感觉区（SII）和位于AG 1内侧和喙侧的内侧无颗粒区。在SI中，标记的细胞主要发现在细胞结构上不同的区域称为SI的dysgranular领域。标记的神经元存在于层II和III，Va和层VI的最深部分在这个领域和在SII。标记细胞也存在于SI的密度颗粒场的Va和VI层中，这是由皮肤输入强烈激活的SI的一部分。对AG 1的连合输入来自对侧AG 1的II-VI层，丘脑输入来自腹外侧核、腹内侧核、后内侧核和中央外侧核。另外的传入纤维来自基底前脑、腹侧丘脑、中脑中缝核和蓝斑的神经元。来自躯体感觉和额叶皮层区域、丘脑运动中心和其他几个皮层下区域的输入AG 1的这种组合意味着AG 1形成感觉运动皮层的细分，其在中枢定向运动以及由躯体感觉反馈引导的运动中是重要的。
Retrograde axonal transport techniques were used to identify the afferent connections of the lateral agranular field (AG1) of the rat frontal cortex. This cytoarchitectonically distinct cortical field forms the bulk of the primary motor cortex (MI) as defined by intracortical microstimulation studies. Following injections of horseradish peroxidase (HRP) or wheat germ agglutinin conjugated to HRP into AG1, retrogradely labeled cells are found in the forebrain, thalamus and brainstem. Within the cerebral cortex labeled neurons are mainly present in the 1st somatic sensory area (SI), the 2nd somatic sensory area (SII) and the medial agranular field, which lies medial and rostral to AG1. In SI, labeled cells are found primarily in a cytoarchitecturally distinct region called the dysgranular field of SI. Labeled neurons are present in layers II and III, Va and the deepest part of layer VI in this field and in SII. Labeled cells are also present in layers Va and VI of the density granular field of SI, which is the part of SI that is strongly activated by cutaneous inputs. Commissural inputs to AG1 arise from layers II-VI of the contralateral AG1 and thalamic inputs arise from the ventrolateral, ventromedial, posterior medial and central lateral nuclei. Additional afferent fibers originate from neurons in the basal forebrain, the ventral thalamus, the midbrain raphe nuclei and the locus coeruleus. This combination of inputs AG1 from somatic sensory and frontal cortical fields, thalamic motor centers and several other subcortical areas implies that AG1 forms a subdivision of sensorimotor cortex that is important in centrally directed movements as well as those that are guided by somatic sensory feedback.