Simerly R B, Swanson L W
Howard Hughes Medical Institute, Salk Institute for Biological Studies, La Jolla, California 92037.
J Comp Neurol. 1988 Apr 8;270(2):209-42. doi: 10.1002/cne.902700205.
The projections of the medial preoptic nucleus (MPN) were examined by making injections of the anterogradely transported lectin Phaseolus vulgaris leucoagglutinin (PHA-L) into the MPN and charting the distribution of labeled fibers. The evidence indicates that the MPN projects extensively to widely distributed regions in both the forebrain and brainstem, most of which also supply inputs to the nucleus. An important neuroendocrine role for the MPN is underscored by its extensive projections to almost all parts of the periventricular zone of the hypothalamus, including the anteroventral periventricular, anterior part of the periventricular, paraventricular (PVH), and arcuate nuclei, and a role in autonomic mechanisms is indicated by projections to such regions as the dorsal and lateral parvicellular parts of the PVH, the lateral parabrachial nucleus, and the nucleus of the solitary tract. Other projections of the MPN suggest participation in the initiation of specific motivated behaviors. For example, inputs to two nuclei of the medial zone of the hypothalamus, the ventromedial and dorsomedial nuclei, may be related to the control of reproductive and ingestive behaviors, respectively, although the possible functional significance of a strong projection to the ventral premammillary nucleus is presently unclear. The execution of these behaviors may involve activation of somatomotor regions via projections to the substantia innominata, zona incerta, ventral tegmental area, and pedunculopontine nucleus. Similarly, inputs to other regions that project directly to the spinal cord, such as the periaqueductal gray, the laterodorsal tegmental nucleus, certain medullary raphe nuclei, and the magnocellular reticular nucleus may also be involved in modulating somatic and/or autonomic reflexes. Finally, the MPN may influence a wide variety of physiological mechanisms and behaviors through its massive projections to areas like the ventral part of the lateral septal nucleus, the bed nucleus of the stria terminalis, the lateral hypothalamic area, the supramammillary nucleus, and the ventral tegmental area, all of which have extensive connections with regions along the medial forebrain bundle. Although the PHA-L method does not allow a clear demonstration of possible differential projections from each subdivision of the MPN, our results suggest that each of them does give rise to a unique pattern of outputs.(ABSTRACT TRUNCATED AT 400 WORDS)
通过将顺行运输的凝集素菜豆白细胞凝集素（PHA-L）注射到内侧视前核（MPN）中并绘制标记纤维的分布，来研究内侧视前核的投射。证据表明，内侧视前核广泛投射到前脑和脑干中广泛分布的区域，其中大多数区域也向该核提供输入。内侧视前核广泛投射到下丘脑室周区的几乎所有部分，包括室周前腹侧、室周前部、室旁核（PVH）和弓状核，这突出了其重要的神经内分泌作用；而其投射到室旁核的背侧和外侧小细胞部分、外侧臂旁核和孤束核等区域，则表明其在自主神经机制中发挥作用。内侧视前核的其他投射表明其参与特定动机行为的启动。例如，内侧视前核投射到下丘脑内侧区的两个核团，即腹内侧核和背内侧核，可能分别与生殖行为和摄食行为的控制有关，尽管目前尚不清楚其向腹侧乳头前核的强烈投射可能具有的功能意义。这些行为的执行可能涉及通过投射到无名质、未定带、腹侧被盖区和脚桥核来激活躯体运动区域。同样，内侧视前核投射到其他直接投射到脊髓的区域，如导水管周围灰质、背外侧被盖核、某些延髓中缝核和巨细胞网状核，也可能参与调节躯体和/或自主反射。最后，内侧视前核可能通过其大量投射到外侧隔核腹侧部分、终纹床核、外侧下丘脑区、乳头体上核和腹侧被盖区等区域，影响多种生理机制和行为，所有这些区域都与内侧前脑束沿线的区域有广泛联系。尽管PHA-L方法无法清楚地显示内侧视前核各亚区可能存在的差异投射，但我们的结果表明，它们各自确实产生了独特的输出模式。（摘要截选至400字）
