Palkovits M, Mezey E, Eskay R L
Laboratory of Cell Biology, National Institute of Mental Health, Bethesda, MD 20892.
Brain Res. 1987 Dec 15;436(2):323-38. doi: 10.1016/0006-8993(87)91676-3.
Relatively high concentrations of adrenocorticotropic hormone (ACTH), beta-endorphin and alpha-melanocyte-stimulating hormone (alpha-MSH) were determined by radioimmunoassay in the nucleus of the solitary tract (NTS) of rats. Dense networks of immunoreactive fibers for these peptides were most prominent in the commissural part of the nucleus, where immunostained perikarya (8-15 per section) were also seen in colchicine-treated rats. Moderate peptide levels and moderately dense immunoreactive networks of these peptides were found in the lateral reticular nucleus (including the A1 and A5-C1 catecholaminergic cell groups) and the nucleus ambiguus. Ten different types of surgical lesions or transections were performed in the hypothalamus and the lower brainstem to determine the origin of ACTH, beta-endorphin and alpha-MSH in the brainstem baroreceptor centers. Except the commissural part of the NTS, the baroreceptor areas receive ACTH, beta-endorphin and alpha-MSH innervations from both the hypothalamic arcuate cells and local neurons in the NTS. Fibers in the commissural part of the NTS seem to be of local origin. Hypothalamic fibers to the rostral part of the NTS and the vasomotor A5-C1 cell groups descend in both a medial (through the periaqueductal central gray) and a lateral (ventrolateral tegmental fibers) pathway, whereas fibers to the caudal lateral reticular nucleus (A1 cell group) and the nucleus ambiguus may run only in the lateral pathway. The descending fibers may decussate somewhere in the caudal hypothalamus-rostral midbrain, but caudal to that level they run and terminate ipsilaterally. Fibers from the ACTH-, beta-endorphin- and alpha-MSH-containing cells in the NTS form a bundle arching between the NTS and the ventrolateral medulla and partially (40-55%) innervate the vasomotor and the vasodepressor areas, as well as the nucleus ambiguus.
通过放射免疫分析法测定，大鼠孤束核（NTS）中促肾上腺皮质激素（ACTH）、β-内啡肽和α-黑素细胞刺激素（α-MSH）的浓度相对较高。这些肽的免疫反应性纤维密集网络在核的连合部最为突出，在秋水仙碱处理的大鼠中，每切片还可见8 - 15个免疫染色的核周体。在外侧网状核（包括A1和A5 - C1儿茶酚胺能细胞群）和疑核中发现了这些肽的中等水平和中等密集的免疫反应性网络。在下丘脑和脑干下部进行了十种不同类型的手术损伤或横切，以确定脑干压力感受器中心中ACTH、β-内啡肽和α-MSH的来源。除了NTS的连合部，压力感受器区域接受来自下丘脑弓状细胞和NTS中局部神经元的ACTH、β-内啡肽和α-MSH神经支配。NTS连合部的纤维似乎是局部起源的。到达NTS前部和血管运动性A5 - C1细胞群的下丘脑纤维通过内侧（穿过导水管周围中央灰质）和外侧（腹外侧被盖纤维）两条途径下行，而到达尾侧外侧网状核（A1细胞群）和疑核的纤维可能仅走行于外侧途径。下行纤维可能在尾侧下丘脑 - Rostral中脑的某处交叉，但在该水平以下它们同侧走行并终止。来自NTS中含ACTH、β-内啡肽和α-MSH细胞的纤维形成一束，在NTS和腹外侧髓质之间呈弓形，部分（40 - 55%）支配血管运动和血管减压区域以及疑核。
