Shostak S, Adams J A
J Exp Zool. 1975 Apr;192(1):43-56. doi: 10.1002/jez.1401920106.
The morphogenesis of so-called secondary (2 degree) heads, budding regions and feet, and separations at graft borders, is studied in multiple-graft animals containing three gastric regions (3g animals) treated with Colcemid or colchicine. Control animals consist of three non-treated pieces. Animals consisting of two non-treated and one treated piece are also employed. The main effects of Colcemid are the promotion of graft healing at the distal graft border, and of 2 degree head formation on the proximal gastric region (g-1). Colchicine also promotes graft healing at the distal graft border, but in contrast to the effect of Colcemid, promotes the formation of ectopic feet (tertiary feet) and inhibits head regeneration at the distal end of the middle gastric region (g-2). Colchicine also accelerates an inversion of polarity in 2 degree budding regions on the g-2 pieces of animals with 2 degree heads on their g-1 pieces. Treatment of a distal graft piece with Colcemid promotes 2 degree head formation on the nearest proximal piece which is not treated, but the inhibition of 2 degree head formation by colchicine occurs only on colchicine treated pieces. The morphogenetic effects of the drugs are interpreted as consequences of their actions on nerve differentiation and cell division. The paper argues that homeostatic control of a hydra's cell population depends on dividing cells influencing cell loss, and that similar mechanisms are involved in the rejection of a graft and the separation of a bud.
在接受秋水仙酰胺或秋水仙碱处理的包含三个胃区的多移植动物（3g动物）中，研究了所谓二级头部、芽区和足部的形态发生，以及移植边界处的分离情况。对照动物由三个未处理的片段组成。还使用了由两个未处理片段和一个处理片段组成的动物。秋水仙酰胺的主要作用是促进移植远端边界处的移植愈合，以及促进近端胃区（g - 1）上二级头部的形成。秋水仙碱也促进移植远端边界处的移植愈合，但与秋水仙酰胺的作用相反，它促进异位足部（三级足部）的形成，并抑制胃中区（g - 2）远端的头部再生。秋水仙碱还加速了g - 1片段上有二级头部的动物的g - 2片段上二级芽区的极性反转。用秋水仙酰胺处理移植远端片段可促进最近的未处理近端片段上二级头部的形成，但秋水仙碱对二级头部形成的抑制仅发生在经秋水仙碱处理的片段上。这些药物的形态发生作用被解释为它们对神经分化和细胞分裂作用的结果。本文认为，水螅细胞群体的稳态控制取决于分裂细胞对细胞损失的影响，并且类似的机制参与了移植排斥和芽体分离。
