Ito K, Morita T
Department of Biology, Faculty of Science, Osaka University, Japan.
Dev Dyn. 1995 Oct;204(2):211-8. doi: 10.1002/aja.1002040212.
This study examines the role of retinoic acid (RA) in mouse neural crest cell development in culture. We have compared the effects of RA on the developmental behavior of mouse neural crest cells from different axial levels, that is the mesencephalic (cranial) and sympathoadrenal (trunk) levels by colony assay using antibodies against cell-type-specific markers. In control cultures in the absence of RA, the efficiency of colony formation by cranial neural crest cells was considerably lower than in colony cultures of trunk neural crest cells. Pulse-labelling experiments using 5-bromo-2'-deoxyuridine (BrdU) showed that the proportion of neural crest cells that incorporated BrdU was significantly smaller in day 5 cultures of cranial neural crest cells in the absence of RA compared to cultures from the trunk level. However, BrdU-incorporation matched the labelling observed in trunk crest cell cultures when RA was added to the culture medium. The efficiency of colony formation and the proportion of BrdU-incorporated cells in trunk crest cell cultures was similar in the presence and absence of RA. The results suggest that in the early stages of in vitro development, RA has a larger impact on proliferation and/or survival of cranial neural crest cells than of trunk neural crest cells. Moreover, the data indicate that RA significantly affects melanogenesis and the differentiation of serotonergic neurons in mouse neural crest cell cultures from both axial levels. Whereas melanogenesis was suppressed by RA treatment, serotonergic neurogenesis was promoted. Double-labelling experiments with antibodies against BrdU and serotonin (5-HT) indicated that RA selectively promoted proliferation of these neurons at a later stage of in vitro development. Furthermore, RA acted upon both committed cells and multipotent cells, Based on the results, we conclude that RA plays multiple critical roles in mouse neural crest cell development.
本研究考察了视黄酸(RA)在培养的小鼠神经嵴细胞发育中的作用。我们通过使用针对细胞类型特异性标志物的抗体进行集落分析,比较了RA对来自不同轴向水平(即中脑(颅部)和交感肾上腺(躯干)水平)的小鼠神经嵴细胞发育行为的影响。在无RA的对照培养物中,颅神经嵴细胞的集落形成效率明显低于躯干神经嵴细胞的集落培养物。使用5-溴-2'-脱氧尿苷(BrdU)进行的脉冲标记实验表明,在无RA的情况下,第5天的颅神经嵴细胞培养物中掺入BrdU的神经嵴细胞比例明显小于来自躯干水平的培养物。然而,当向培养基中添加RA时,BrdU掺入量与在躯干嵴细胞培养物中观察到的标记情况相匹配。在有或无RA的情况下,躯干嵴细胞培养物中的集落形成效率和掺入BrdU的细胞比例相似。结果表明,在体外发育的早期阶段,RA对颅神经嵴细胞增殖和/或存活的影响比对躯干神经嵴细胞的影响更大。此外,数据表明RA对来自两个轴向水平的小鼠神经嵴细胞培养物中的黑色素生成和血清素能神经元分化有显著影响。RA处理抑制黑色素生成,而促进血清素能神经发生。用抗BrdU和血清素(5-HT)抗体进行的双重标记实验表明,RA在体外发育的后期选择性地促进了这些神经元的增殖。此外,RA作用于定向细胞和多能细胞。基于这些结果,我们得出结论,RA在小鼠神经嵴细胞发育中发挥着多种关键作用。