Schaller H Chica
Mikrobiologie, Universität Heidelberg, Im Neuenheimer Feld 280 (DKFZ), 6900, Heidelberg, Germany.
European Molecular Biology Laboratory, Im Neuenheimer Feld 280 (DKFZ), 6900, Heidelberg, Germany.
Wilehm Roux Arch Dev Biol. 1976 Dec;180(4):287-295. doi: 10.1007/BF00848775.
Hydra regenerating heads release at least two substances into the surrounding medium: one stimulates and one inhibits head formation. The inhibitor is released mainly during the first hour after cutting, the activator is released more slowly with a maximum in the second hour and with substantial release still during the following six hours. The release of both substances seems to be specific for head regeneration: it is not found in animals regenerating feet. The sequential release of these substances leads to the early changes observed at the cellular level during head regeneration inhydra: the inhibitor produces a decrease, the activator an increase in the mitotic activity of interstitial and epithelial cells, if assayed on intact animals. Head regeneration is blocked, if the release of the head activator is prevented. It is therefore suggested that these substances are necessary to initiate head regeneration inhydra.
一种刺激头部形成，一种抑制头部形成。抑制剂主要在切割后的第一个小时内释放，激活剂释放得较慢，在第二个小时达到最大值，并且在接下来的六个小时内仍有大量释放。这两种物质的释放似乎对头再生具有特异性：在再生足部的动物中未发现。这些物质的顺序释放导致了水螅头部再生过程中在细胞水平上观察到的早期变化：如果在完整动物上进行检测，抑制剂会使间质细胞和上皮细胞的有丝分裂活性降低，激活剂则会使其增加。如果阻止头部激活剂的释放，头部再生就会受阻。因此，有人认为这些物质是启动水螅头部再生所必需的。
