Carabba V H, Sorokin S P, Hoyt R F
Am J Anat. 1985 May;173(1):1-27. doi: 10.1002/aja.1001730102.
Intact, 14- to 21-day fetal rat lung pairs, neonatal lungs, and cultured 15- and 16-day lung explants were examined in 2-micron-thick glycol methacrylate sections stained by PAS-lead hematoxylin. Selected stages were also studied in histochemical preparations for aliesterase and formaldehyde-induced monoamine fluorescence, as well as by scanning and transmission electron microscopy. Neuroepithelial bodies (NEBs) first appear in pseudoglandular lungs at 15 days in vivo as pyramidal groups of basal, diffusely lead-hematoxylin-positive cells in glycogen-depleted epithelium of main and lobar bronchi. By day 16, primitive NEBs occur within three to four generations of the terminal buds, and older, proximal bodies are larger and more distinctive than at 15 days. Aliesterase activity is first detected in basally located, developing NEBs on day 16. During the canalicular and alveolar sac periods, NEBs appear and mature on a proximal-to-distal gradient along the airway, as they do in developing rabbit and human lungs. As earlier-formed airways elongate, additional NEBs appear and supplement the population already present. By days 20-21, NEBs occur at all airway levels down to the bronchiolo-alveolar junctions, and many of the cells have discrete PAS- and lead-hematoxylin-positive, infranuclear granules. Near term some NEBs exhibit serotonin fluorescence after incubation in 5-hydroxytryptophan and have abundant, ca. 100-nm, electron-dense granules. These are concentrated toward the cell base like the stained granules visualized by light microscopy. Similar results were obtained from lungs placed in organ culture. From 2 days in culture to a time equivalent to term, NEB formation parallels that in vivo, indicating that developmental requirements are met in in vitro. Taken altogether, morphologic and cytochemical evidence suggests that NEBs of rats are functional in late fetal life and that their development is relatively independent of extrapulmonary influences and of the intraepithelial ingrowth of sensory nerve endings.
对完整的14至21天胎鼠肺叶、新生鼠肺以及培养的15和16天肺组织块进行检查，制作2微米厚的甲基丙烯酸乙二醇酯切片，用PAS-铅苏木精染色。还对选定阶段进行了组织化学制备，以检测酯酶和甲醛诱导的单胺荧光，并通过扫描和透射电子显微镜进行研究。神经上皮小体（NEBs）在体内15天时首次出现在假腺期肺中，呈锥形群，位于主支气管和叶支气管糖原缺乏上皮中的基底、弥漫性铅苏木精阳性细胞。到16天时，原始NEBs出现在终末芽的三到四代内，较老的近端小体比15天时更大且更明显。酯酶活性在16天时首次在位于基底的发育中的NEBs中检测到。在小管期和肺泡囊期，NEBs沿气道从近端到远端呈梯度出现并成熟，就像在发育中的兔肺和人肺中一样。随着早期形成的气道延长，额外的NEBs出现并补充已有的群体。到20至21天时，NEBs出现在直至细支气管肺泡交界处的所有气道水平，许多细胞具有离散的PAS和铅苏木精阳性的核下颗粒。接近足月时，一些NEBs在5-羟色氨酸孵育后呈现血清素荧光，并具有丰富的约100纳米的电子致密颗粒。这些颗粒像光镜下观察到的染色颗粒一样集中在细胞基部。从置于器官培养中的肺也获得了类似结果。从培养2天到相当于足月的时间，NEBs的形成与体内情况相似，表明体外培养满足了发育需求。总体而言，形态学和细胞化学证据表明，大鼠的NEBs在胎儿后期具有功能，并且它们的发育相对独立于肺外影响和感觉神经末梢的上皮内生长。
