Otto J J, Campbell R D
J Cell Sci. 1977 Dec;28:117-32. doi: 10.1242/jcs.28.1.117.
Epithelial cell production and epithelial cell loss in 6 different size classes of Hydra attenuata were examined to understand the relationships between growth and morphogenesis. The sizes of adult hydra, the sizes of their buds, and their budding rates are all nearly proportional to the amount of food the hydra eat. Hydra fed at high rates (4-25 Artemia nauplii per day) all have the same epithelial cell cycle time (about 4 days). Budding accounts for most of their cell loss. Hydra fed 4-12 Artemia per day maintain a steady state condition in which tissue loss balances tissue growth. Animals fed 25 Artemia per day are not in a steady state growth condition and change in size. At the lowest feeding rates (0-1 Artemia per day), the epithelial cell cycle time is lengthened to about 16 days. Cell loss from the tentacles accounts for most of the cell loss, and this loss is not completely balanced by growth. As a consequence these animals cease budding and shrink in size.
为了理解生长与形态发生之间的关系，研究人员对6种不同大小类别的细螅（Hydra attenuata）的上皮细胞生成和上皮细胞损失情况进行了检查。成年细螅的大小、其芽体的大小以及它们的出芽率都几乎与细螅所摄取食物的量成正比。以高摄食率（每天4 - 25只卤虫无节幼体）进食的细螅，其上皮细胞周期时间均相同（约4天）。出芽是其细胞损失的主要原因。每天喂食4 - 12只卤虫的细螅维持着一种稳态，即组织损失与组织生长达到平衡。每天喂食25只卤虫的动物处于非稳态生长状态，其大小会发生变化。在最低摄食率（每天0 - 1只卤虫）下，上皮细胞周期时间延长至约16天。触手的细胞损失占细胞损失的大部分，且这种损失并未完全被生长所平衡。因此，这些动物停止出芽并体型缩小。
