Velayos J L, Jiménez-Castellanos J, Reinoso-Suárez F
Departamento de Morfología, Facultade de Medicina, Universidad Autónoma de Madrid, Spain.
J Comp Neurol. 1989 Jan 15;279(3):457-69. doi: 10.1002/cne.902790310.
The topography of the projections from the reticular nucleus of the thalamus (RT) to the intralaminar and medial thalamic nuclei were studied in the cat by the method of retrograde transport of horseradish peroxidase (HRP). Single small injections of the enzyme were made in the different intralaminar nuclei--mediodorsal, ventromedial, midline, and habenular--and in anterior group nuclei. The location and density of the neuronal labeling in the different parts of the RT were studied in each case. Our results show that 1) after injections located in all the nuclei here studied, a consistent number of labeled neurons were found in the RT, except for the injections in the lateral habenula and the anterior thalamic nuclear complex, both of which did not label neurons in the RT. 2) Among the other thalamic nuclei here studied, the most medially situated receive less numerous RT projections than those most laterally located. 3) Injections in all the nuclei studied gave rise to a cellular labeling in the anterior sectors of the RT, except for the anterior nuclear group and the lateral habenula. The projections from the rostral pole of the RT were topographically mediolaterally organized. 4) The anterodorsal part of the pregeniculate sector of the RT projects upon the large-celled part of the lateral central nucleus and to a lesser extent upon the paracentral, centromedian, and ventromedial nuclei, the anterior part of the lateral central nucleus, and the lateral band of the mediodorsal nucleus. The posterodorsal part of the RT pregeniculate sector only projects to the large-celled part of the lateral central nucleus. The dorsal portion of the posteroventral part of the RT pregeniculate sector also projects upon the large-celled part of the lateral central nucleus; its ventral portion projects to the ventromedial nucleus, the posterior part of the paracentral nucleus, the lateral band of the mediodorsal nucleus, and the centromedian nucleus. 5) The infrageniculate sector of the RT projects to the posterior part of the ventromedial nucleus. A weaker projection to the large-celled part of the lateral central nucleus, the centromedian nucleus, and the lateral band of the mediodorsal nucleus was also observed. 6) The ventral lateral geniculate nucleus projects upon the large-celled part of the lateral central nucleus, the lateral band of the mediodorsal nucleus, and the ventromedial nucleus. All these findings suggest an important modulatory action of the RT on the activity of the thalamic nuclei considered here.
采用辣根过氧化物酶（HRP）逆行运输法，在猫身上研究了丘脑网状核（RT）向丘脑板内核和内侧核的投射拓扑结构。将酶单次少量注射到不同的板内核——背内侧核、腹内侧核、中线核和缰核——以及前组核中。在每种情况下，研究RT不同部位神经元标记的位置和密度。我们的结果表明：1）在所有此处研究的核团中进行注射后，除了在外侧缰核和丘脑前核复合体中进行的注射外，在RT中均发现了一定数量的标记神经元，而这两种注射均未标记RT中的神经元。2）在其他此处研究的丘脑中，最内侧的核团比最外侧的核团接受的RT投射数量更少。3）除了前核群和外侧缰核外，在所有研究的核团中进行注射均在RT的前部产生细胞标记。RT嘴侧极的投射在拓扑结构上呈内侧-外侧排列。4）RT膝前区的前背侧部分投射到外侧中央核的大细胞部分，在较小程度上投射到中央旁核、中央中核、腹内侧核、外侧中央核的前部以及背内侧核的外侧带。RT膝前区的后背侧部分仅投射到外侧中央核的大细胞部分。RT膝前区后腹侧部分的背侧部分也投射到外侧中央核的大细胞部分；其腹侧部分投射到腹内侧核、中央旁核的后部、背内侧核的外侧带和中央中核。5）RT膝下区投射到腹内侧核的后部。还观察到对外侧中央核的大细胞部分、中央中核和背内侧核外侧带的较弱投射。6）腹外侧膝状核投射到外侧中央核的大细胞部分、背内侧核的外侧带和腹内侧核。所有这些发现表明RT对这里所考虑的丘脑核团的活动具有重要的调节作用。
