Slenzka K, Appel R, Rahmann H
University of Stuttgart-Hohenheim, Institute of Zoology, Germany.
Neurochem Int. 1993 Apr;22(4):405-11. doi: 10.1016/0197-0186(93)90022-w.
The development of creatine kinase (CK) activity was studied in the brain of cichlid fish and clawed toads. The activity of CK in the whole brain of the fish decreases immediately after hatching (stage 6) from values of about 135 nmol substrate cleaved/mg protein/min to a value of about 105 at stage 8 (5 days post hatch at 20 degrees C). With the exception of a significant peak (125 nmol) between stages 9 and 10 (7 and 9 days respectively, post hatch at 20 degrees C) and a small intermediate peak at stages 12 and 13 (about 10 days post hatch at 20 degrees C) a constant level of about 100 nmol cleaved substrate is maintained until maturity. In contrast, CK activity was determined to be 3-fold higher in the whole brain of the clawed toad. With the exception of two significant peaks at stages 47 and 49 (5 and 12 days respectively, post fertilization at 23 degrees C) a value of about 360 nmol was found during larval development and metamorphosis, as well as in the adult brain. In investigating the possible influence of gravity on CK activity during early ontogeny of the brain both animal species were exposed to hyper-gravity (3 +/- 1 g) for 7 days. A significant decrease of total CK activity of 20% was found in the fish brain and of about 5% in the toad.(ABSTRACT TRUNCATED AT 250 WORDS)
研究了丽鱼科鱼类和爪蟾大脑中肌酸激酶（CK）活性的发展情况。孵化后（第6阶段），鱼类全脑的CK活性立即从约135 nmol底物裂解/mg蛋白质/分钟降至第8阶段（20℃下孵化后5天）的约105 nmol。除了在第9和第10阶段（分别为孵化后7天和9天，20℃下）有一个显著峰值（125 nmol）以及在第12和第13阶段（20℃下孵化后约10天）有一个小的中间峰值外，约100 nmol裂解底物的恒定水平一直维持到成熟。相比之下，爪蟾全脑的CK活性测定值高出3倍。除了在第47和第49阶段（分别为受精后5天和12天，23℃下）有两个显著峰值外，在幼体发育、变态以及成体大脑中均发现约360 nmol的值。在研究重力对大脑早期个体发育过程中CK活性的可能影响时，两种动物都暴露于超重力（3±1 g）环境7天。结果发现，鱼脑总CK活性显著下降20%，蟾蜍脑总CK活性下降约5%。（摘要截于250字）
