Kawano H, Masuko S
Department of Anatomy, Saga Medical School, Japan.
Neurosci Lett. 1996 Oct 25;218(1):33-6. doi: 10.1016/0304-3940(96)13115-3.
We used light and electron microscopic techniques to investigate the possibility that neurons in the nucleus of the solitary tract (NST) might send projection fibers to neurons in the caudal ventrolateral medulla (CVLM) projecting to the paraventricular hypothalamic nucleus (PVN) by the anterograde and retrograde double labeling method in the rat. The retrograde tracer, wheat germ agglutinin-conjugated horseradish peroxidase-colloidal gold complex, was injected into the PVN, and the anterograde tracer, Phaseolus vulgaris leucoagglutinin (PHA-L), was injected into the NST of each rat. Many retrogradely labeled neurons were encountered in the CVLM, including the A1 region. On the other hand, a dense network of anterogradely labeled terminals was found in the CVLM. Electron microscopic examination revealed synaptic contacts between PHA-L-immunoreactive nerve terminals and dendrites of retrogradely labeled neurons in the CVLM. The results indicate that CVLM neurons projecting to the PVN receive axon terminals of NST neurons.
我们采用光镜和电镜技术，运用顺行和逆行双重标记法，研究大鼠孤束核（NST）中的神经元是否可能向尾侧腹外侧延髓（CVLM）中投射至室旁下丘脑核（PVN）的神经元发送投射纤维。将逆行示踪剂——小麦胚凝集素结合辣根过氧化物酶-胶体金复合物注入PVN，并将顺行示踪剂——菜豆白细胞凝集素（PHA-L）注入每只大鼠的NST。在CVLM（包括A1区）中发现了许多逆行标记的神经元。另一方面，在CVLM中发现了密集的顺行标记终末网络。电镜检查显示，在CVLM中，PHA-L免疫反应性神经终末与逆行标记神经元的树突之间存在突触联系。结果表明，投射至PVN的CVLM神经元接受NST神经元的轴突终末。
