Halsell C B, Travers S P, Travers J B
College of Dentistry, Ohio State University, Columbus 43210, USA.
Neuroscience. 1996 May;72(1):185-97. doi: 10.1016/0306-4522(95)00528-5.
Anterograde studies have shown that neurons within the rostral (gustatory) nucleus of the solitary tract project to the parabrachial nucleus, as well as to sites within the medulla including the reticular formation and caudal nucleus of the solitary tract. In order to determine the degree to which the same neurons contribute to both projections, injections of retrograde tracers were made simultaneously into both the parabrachial nuclei and medullary reticular formation of the rat. Only a small proportion of neurons were double labeled. Consistent with studies in hamster, labeled neurons projecting to the parabrachial nuclei in rat consisted of both stellate and elongate neurons, concentrated within the central subdivision of the rostral nucleus of the solitary tract. Injections into the medullary reticular formation also labeled both stellate and elongate neurons but these were concentrated in the ventral subdivision of the nucleus. The results of the present study demonstrate that different populations of neurons in the nucleus of the solitary tract contribute to ascending and descending pathways. This suggest a possible functional specialization within the nucleus of the solitary tract for those neurons whose output eventually reaches the forebrain compared to those neurons with local connections.
顺行性研究表明，孤束吻侧（味觉）核内的神经元投射至臂旁核，以及延髓内的一些部位，包括网状结构和孤束尾侧核。为了确定同一神经元对这两种投射的贡献程度，将逆行示踪剂同时注射到大鼠的臂旁核和延髓网状结构中。只有一小部分神经元被双重标记。与对仓鼠的研究一致，大鼠中投射至臂旁核的标记神经元包括星状神经元和细长神经元，集中在孤束吻侧核的中央亚区。注射到延髓网状结构中也标记了星状神经元和细长神经元，但这些神经元集中在该核的腹侧亚区。本研究结果表明，孤束核中不同群体的神经元参与了上行和下行通路。这表明，与那些具有局部连接的神经元相比，孤束核中那些输出最终到达前脑的神经元可能存在功能特化。
