Department of Human Medicine, MSH Medical School Hamburg - University of Applied Sciences and Medical University, Hamburg, Germany.
Department of Human Medicine, MSH Medical School Hamburg - University of Applied Sciences and Medical University, Hamburg, Germany; Institute of Anatomy II, Friedrich-Schiller-University Jena, Germany.
J Chem Neuroanat. 2021 Jan;111:101882. doi: 10.1016/j.jchemneu.2020.101882. Epub 2020 Nov 4.
The hypothalamic neuropeptides oxytocin (OT) and arginine-vasopressin (AVP) are important factors involved in the control of socio-emotional behaviors via their modulation of amygdala functions. Since anatomical pathways of magnocellular projections to limbic structures in the human brain have not been dissected, we infused ethanol-dissolved tracer DiI into three amygdala nuclei - medial, central and lateral nuclei, and into the mammillary bodies of postmortem fixed human brains. With this modification, lipophilic diffusion of DiI occurred much faster than with conventional DiI crystals. After staining of resliced sections with antibodies against OT or AVP, we detected DiI/OT-positive neurons and their axons, specifically in the supraoptic nucleus (SON), but not in other hypothalamic nuclei producing OT or AVP. DiI fluorescence was found in the lateral portion of the paraventricular nucleus (PVN) and in the fornix columns, together with VP- immunoreactivity, only after DiI injections into the mammillary bodies. Our findings indicate that OT and AVP may have distinct neuronal pathways to the limbic system, and they are different from those previously reported in rodents.
下丘脑神经肽催产素（OT）和精氨酸加压素（AVP）是通过调节杏仁核功能参与社会情感行为控制的重要因素。由于人类大脑的大细胞投射到边缘结构的解剖途径尚未被剖析，我们将溶于乙醇的示踪剂 DiI 注入到三个杏仁核核 - 内侧核、中央核和外侧核，以及死后固定人脑的乳头体中。通过这种改良，DiI 的亲脂扩散速度比传统 DiI 晶体快得多。在用针对 OT 或 AVP 的抗体对重新切片的组织进行染色后，我们检测到 DiI/OT 阳性神经元及其轴突，特别是在视上核（SON）中，但在产生 OT 或 AVP 的其他下丘脑核中没有。只有在向乳头体注射 DiI 后，才能在室旁核（PVN）的外侧部分和穹窿柱中，以及 VP-免疫反应性中发现 DiI 荧光。我们的发现表明，OT 和 AVP 可能有到边缘系统的不同神经元途径，与以前在啮齿动物中报道的途径不同。
