Negatu Z, Meier A H
Department of Zoology and Physiology, Louisiana State University, Baton Rouge 70803, USA.
Gen Comp Endocrinol. 1995 May;98(2):193-201. doi: 10.1006/gcen.1995.1060.
The effect of recombinant human insulin-like growth factor I (rhIGF-I) on protein synthesis was studied in vitro in the muscle of a teleost fish. Protein synthesis was assessed by the incorporation of [14C]glycine into protein. rhIGF-I stimulated [14C]glycine incorporation in a dose-dependent manner. The minimal effective dose was 0.1 ng/ml and maximal stimulation was obtained with 1 ng/ml. A high concentration (100 ng/ml) was ineffective. Treatment with 1 ng/ml rhIGF-I produced a significant response after 3 hr of incubation and the greatest stimulation was observed after 6 hr. Responsiveness of muscle tissue to IGF-I examined at three different times (0, 6, and 12 hr after light onset, LD 12:12) was greatest at light onset. These results provide evidence that IGF-I may have a role in the regulation of growth in fish and that its activities are dose and time-of-day dependent.
在硬骨鱼的肌肉中对重组人胰岛素样生长因子I（rhIGF-I）对蛋白质合成的影响进行了体外研究。通过将[14C]甘氨酸掺入蛋白质中来评估蛋白质合成。rhIGF-I以剂量依赖的方式刺激[14C]甘氨酸掺入。最小有效剂量为0.1 ng/ml，1 ng/ml时获得最大刺激。高浓度（100 ng/ml）无效。用1 ng/ml rhIGF-I处理在孵育3小时后产生显著反应，6小时后观察到最大刺激。在三个不同时间（光照开始后0、6和12小时，光暗周期12:12）检查的肌肉组织对IGF-I的反应性在光照开始时最大。这些结果提供了证据，表明IGF-I可能在鱼类生长调节中起作用，并且其活性依赖于剂量和一天中的时间。
