Teratologic effects of Bis-diamine on cardiovascular development in rat embryo : in vivo and in vitro analysis

双二胺给药可引起妊娠大鼠锥体异常。为了了解双二胺对发育阶段的致畸作用，我们检查了Wister母鼠的新生儿和胚胎，在妊娠10、11或12天（分别为1、2和3组）给予单剂量200 mg双二胺。1组（86例）新生儿主动脉弓异常率为100%，2组（95例）和3组（108例）新生儿主动脉弓异常和社区动脉干异常率为92.8%，主动脉弓异常和法洛四联症分别为45.4%。为了检验双二胺的早期形态学影响，我们按照Cockroft和New（1978）描述的程序，每组培养4个胚胎24小时。第1组胚胎显示神经管闭合延迟，心环不成熟，第三、第四和第六Nortek弓未分化。利用抗N-CAM抗体进行免疫组织学研究，发现N-CAM阳性细胞在神经管周围稀疏分布。第2组胚胎心室增大、扩张，流出道弯曲、拉长，血流反流，而对照组没有。此外，其中两个胚胎有部分心包缺损。从神经管到心脏的连续N-CAM免疫阳性链清晰可见，尽管与对照组相比较细。3组胚胎与对照组在形态和循环方面均无差异。这些结果表明，双二胺可能干扰心脏神经嵴或间充质细胞的正常发育和迁移，导致不同发育阶段的心血管异常。

Bis-diamine administration to pregnant rats induces conotruncal anomalies.To know teratologic effects of bis-diamine depending on the developmental stage, we examined neonates and embryos from Wister mother rats to which a single dose of 200 mg his-diamine was administered at 10, 11, or 12 days of gestation (group 1, 2, and 3, respectively). The neonates from group 1 (n 86) had aortjc arch anomalies in 100 %, and those from group 2 (n = 95) and 3 (n = 108) had aortic arch anomalies and truncus arteriosus communis in 92.8%, and aortic arch anomalies and tetralogy of Fallot in 45.4%, respectively. In order to examine the early morphological effects of bis-diamine, we cultured four embryos from each group for 24 hours following the procedures described by Cockroft and New (1978). The embryos from group 1 showed delayed closure of the neural tube and immature cardiac looping with undifferentiated third, fourth, and sixth Nortek arches. Immunohistological study using anti-N-CAM antibody revealed that N-CAM positive cells were sparsely distributed around the neural tube. The embryos from group 2 had an enlarged and dilated ventricle and winding and elongate outflow tract in which regurgitant blood flow was observed, whereas none in controls. Furthermore, two of the embryos had a partial pericardial defect. A continuous N-CAM immunopositive chain from the neural tube to the heart was clearly seen, though thin when compared with controls. No morphological and circulatory difference was seen between embryos from group 3 and controls.These results suggested that bis-diamine may disturb normal development and migration of cardiac neural crest or mesenchymal cells to induce various cardiovascular anomalies depending on the developmental stage.