Hsu L, Jeng A Y
Department of Biology, Seton Hall University, S. Orange, NJ 07079, USA.
Brain Res. 1995 Dec 12;703(1-2):72-8. doi: 10.1016/0006-8993(95)01067-x.
Chick embryos were treated with single or multiple doses of 0-250 pmol of endothelin-1 (ET-1) or endothelin-3 (ET-3) and their effects on development were examined in embryos ranging from 7 to 14 days in age. The overall sizes of the head, trunk, beak or wings were increased (5-14%) in ET-treated embryos. Additionally, the lengths or widths of the telencephalic or optic lobes and the diencephalon in the embryonic brains were also increased (4-14%). These effects were observed when the embryos were treated with ET for three consecutive days beginning on day 2 of incubation or from day 1-5. Similar results were obtained by a single injection given on the 5th day of incubation, but not on day 1 or 3. Morphological studies suggested that ET-1 and ET-3 promoted maturation rather than non-specific growth in size. Histological studies revealed that ET-treated brain tissues were more cellular and organized in appearance than control brains. There was no increased incidence of vascular abnormalities or structural malformations subsequent to ET-treatment. These results suggest that ET has growth factor-like effects and that treatment on and around the 5th day of incubation seemed to be most effective for the early phase in brain development in chick embryos.
用0 - 250皮摩尔的内皮素-1（ET-1）或内皮素-3（ET-3）的单剂量或多剂量处理鸡胚，并在7至14日龄的胚胎中检查它们对发育的影响。经内皮素处理的胚胎的头部、躯干、喙或翅膀的总体大小增加了（5 - 14%）。此外，胚胎大脑中的端脑或视叶以及间脑的长度或宽度也增加了（4 - 14%）。当从孵化第2天开始或从第1 - 5天连续3天用内皮素处理胚胎时，观察到了这些效应。在孵化第5天进行单次注射也获得了类似的结果，但在第1天或第3天注射则没有。形态学研究表明，ET-1和ET-3促进成熟而非非特异性的大小增长。组织学研究显示，经内皮素处理的脑组织在外观上比对照脑更具细胞性且组织结构更完善。内皮素处理后血管异常或结构畸形的发生率没有增加。这些结果表明内皮素有生长因子样作用，并且在孵化第5天及其前后进行处理似乎对鸡胚脑发育的早期阶段最有效。
