Direct projections from caudal ventrolateral medullary depressor sites to the subfornical organ
Direct projections from caudal ventrolateral medullary depressor sites to the subfornical organ
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DOI：
10.1016/j.brainres.2003.12.029
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发表时间：
2004-04-02
期刊：
影响因子：
2.9
通讯作者：
Ciriello, J
中科院分区：
文献类型：
--
作者：
Babic, T;Roder, S;Ciriello, J
本实验在雄性Wistar大鼠上研究了延髓腹外侧区心血管反应部位（VLM）向穹窿下器（SFO）的投射。将菜豆白细胞凝集素（PHA-L）单侧离子电渗注射到尾侧VLM（CVLM）部位，在该部位微量注射L-谷氨酸（10 nl; 0.25 M）引起平均动脉压降低，或注射到吻侧VLM（RVLM）部位，在该部位微量注射L-谷氨酸引起动脉压升高。在7-10天的存活期后，处理前脑和脑干的横切面用于PHA-L免疫反应性。注射PHA-L到CVLM后，轴突和推定的终端标记被发现双边整个rostrocaudal程度的SFO，虽然大部分的预测内观察到的喙侧一半的核。在SFO内，标记主要发现于核的侧面，通常靠近血管。此外，CVLM注射导致终板（OVLT）的血管器内的标记和内侧视前核（MnPO）的腹侧和背侧组件双边，但同侧的优势。相比之下，PHA-L注射到RVLM没有导致轴突标记的SFO或OVLT，虽然一些标记的轴突被发现通过该地区的腹侧组件的MnPO。这些数据表明，在CVLM的心血管反应区的神经元发送直接轴突投射到SFO和终板的其他结构，并建议CVLM可能在调制的室周器官的神经元的活动，以体液平衡的内，外信号的功能。(C)2004 Elsevier B. V.保留所有权利。
Experiments were performed in the male Wistar rat to investigate the projections from cardiovascular responsive sites in the ventrolateral medulla (VLM) to the subfornical organ (SFO). Unilateral iontophoretic injections of Phaseolus vulgaris leucoagglutinin (PHA-L) were made into either caudal VLM (CVLM) sites at which microinjection Of L-glutamate (10 nl; 0.25 M) elicited decreases in mean arterial pressure or into rostral VLM (RVLM) sites at which L-glutamate microinjection elicited increases in arterial pressure. After a survival period of 7-10 days, transverse sections of the forebrain and brainstem, were processed for PHA-L immunoreactivity. After injections of PHA-L into the CVLM, axonal and presumptive terminal labeling was found bilaterally throughout the rostrocaudal extent of the SFO, although most of the projections were observed within the rostral half of the nucleus. Within the SFO, labeling was found primarily in the lateral aspects of the nucleus, often in close proximity to blood vessels. In addition, CVLM injections resulted in labeling within the organum vasculosum of the laminae terminalis (OVLT) and within the ventral and dorsal components of the median preoptic nucleus (MnPO) bilaterally, but with an ipsilateral predominance. In contrast, PHA-L injections into the RVLM did not result in axonal labeling in the SFO or OVLT, although a few labeled axons were found to course through the region of the ventral component of MnPO. These data have demonstrated that neurons within the cardiovascular responsive region of the CVLM send direct axonal projections to the SFO and other structures of the laminae terminalis, and suggest that the CVLM may function in the modulation of the activity of neurons of circumventricular organs to intra- and extracellular signals of body fluid balance. (C) 2004 Elsevier B.V. All rights reserved.