Quartu Marina, Serra Maria Pina, Boi Marianna, Ferretti Maria Teresa, Lai Maria Letizia, Del Fiacco Marina
Department of Cytomorphology, University of Cagliari, Cittadella Universitaria di Monserrato, 09042 Monserrato, Italy.
Brain Res. 2007 Oct 10;1173:36-52. doi: 10.1016/j.brainres.2007.07.064. Epub 2007 Aug 9.
Occurrence and localization of receptor components of the glial cell line-derived neurotrophic factor (GDNF) family ligands, the Ret receptor tyrosine kinase and the GDNF family receptor (GFR) alpha-1 to -3, were examined by immunohistochemistry in the normal human brainstem at fetal, neonatal, and adult age. Immunoreactive elements were detectable at all examined ages with uneven distribution and consistent pattern for each receptor. As a rule, the GFRalpha-1 and GFRalpha-2 antisera produced the most abundant and diffuse tissue labelling. Immunoreactive perikarya were observed within sensory and motor nuclei of cranial nerves, dorsal column nuclei, olivary nuclear complex, reticular formation, pontine nuclei, locus caeruleus, raphe nuclei, substantia nigra, and quadrigeminal plate. Nerve fibers occurred within gracile and cuneate fasciculi, trigeminal spinal tract and nucleus, facial, trigeminal, vestibular and oculomotor nerves, solitary tract, medial longitudinal fasciculus, medial lemniscus, and inferior and superior cerebellar peduncles. Occasionally, glial cells were stained. Age changes were appreciable in the distribution pattern of each receptor. On the whole, in the grey matter, labelled perikarya were more frequently observed in pre- and perinatal than in adult specimens; on the other hand, in discrete regions, nerve fibers and terminals were abundant and showed a plexiform arrangement only in adult tissue; finally, distinct fiber systems in the white matter were immunolabelled only at pre- and perinatal ages. The results obtained suggest the involvement of Ret and GFRalpha receptors signalling in processes subserving both the organization of discrete brainstem neuronal systems during development and their functional activity and maintenance in adult life.
采用免疫组织化学方法，对胎儿、新生儿和成人正常人类脑干中胶质细胞源性神经营养因子（GDNF）家族配体、Ret受体酪氨酸激酶以及GDNF家族受体（GFR）α-1至α-3的受体成分的发生及定位进行了研究。在所有检测年龄均能检测到免疫反应性成分，各受体分布不均但模式一致。通常，GFRα-1和GFRα-2抗血清产生的组织标记最为丰富且弥漫。在脑神经的感觉和运动核、背柱核、橄榄核复合体、网状结构、脑桥核、蓝斑、中缝核、黑质和四叠体板内观察到免疫反应性核周体。神经纤维见于薄束和楔束、三叉神经脊髓束和核、面神经、三叉神经、前庭神经和动眼神经、孤束、内侧纵束、内侧丘系以及小脑上、下脚。偶尔，胶质细胞也被染色。各受体的分布模式存在明显的年龄变化。总体而言，在灰质中，与成人标本相比，在产前和围产期更常观察到标记的核周体；另一方面，在离散区域，神经纤维和终末仅在成人组织中丰富并呈丛状排列；最后，白质中的不同纤维系统仅在产前和围产期被免疫标记。所获得的结果表明，Ret和GFRα受体信号传导参与了发育过程中离散脑干神经元系统的组织以及成体生活中其功能活动和维持的过程。
