Berishvili Giorgi, Shved Natallia, Eppler Elisabeth, Clota Frederic, Baroiller Jean-François, Reinecke Manfred
Division of Neuroendocrinology, Institute of Anatomy, University of Zürich, Zürich, Switzerland.
Cell Tissue Res. 2006 Aug;325(2):287-301. doi: 10.1007/s00441-005-0133-9. Epub 2006 Apr 5.
The cellular sites of insulin-like growth factor I (IGF-I) synthesis in the early developing tilapia (0-140 days post fertilization, DPF) were investigated. IGF-I mRNA and peptide appeared in liver as early as 4 DPF and in gastro-intestinal epithelial cells between 5-9 DPF. In exocrine pancreas, the expression of IGF-I started at 4 DPF and continued until 90 DPF. IGF-I production was detected in islets at 6 DPF in non-insulin cells and occurred throughout life. In renal tubules and ducts, IGF-I production started at 8 DPF. IGF-I production in chondrocytes had its onset at 4 DPF, was more pronounced in growing regions and was also found in adults. IGF-I mRNA and peptide appeared in the cytoplasm of skeletal muscle cells at 4 DPF. In gill chloride cells, IGF-I production started at 6 DPF. At 13 DPF, IGF-I was detected in cardiac myocytes. IGF-I-producing epidermal cells appeared at 5 DPF. In brain and ganglia, IGF-I was expressed in virtually all neurones from 6 to 29 DPF, their number decreasing with age. Neurosecretory IGF-I-immunoreactive axons were first seen in the neurohypophysis around 17 DPF. Endocrine cells of the adenohypophysis exhibited IGF-I mRNA at 28 DPF and IGF-I immunoreactivity at 40 DPF. Thus, IGF-I appeared early (4-5 DPF), first in liver, the main source of endocrine IGF-I, and then in organs involved in growth or metabolism. The expression of IGF-I was more pronounced during development than in juvenile and adult life. Local IGF-I therefore seems to have a high functional impact in early growth, metabolism and organogenesis.
研究了早期发育的罗非鱼（受精后0 - 140天，DPF）中胰岛素样生长因子I（IGF - I）的细胞合成位点。IGF - I mRNA和肽最早在4 DPF时出现在肝脏中，在5 - 9 DPF之间出现在胃肠上皮细胞中。在外分泌胰腺中，IGF - I的表达始于4 DPF并持续至90 DPF。在6 DPF时在胰岛的非胰岛素细胞中检测到IGF - I的产生，并且终生存在。在肾小管和导管中，IGF - I的产生始于8 DPF。软骨细胞中IGF - I的产生始于4 DPF，在生长区域更为明显，在成体中也有发现。IGF - I mRNA和肽在4 DPF时出现在骨骼肌细胞的细胞质中。在鳃氯细胞中，IGF - I的产生始于6 DPF。在13 DPF时，在心肌细胞中检测到IGF - I。产生IGF - I的表皮细胞在5 DPF时出现。在脑和神经节中，从6至29 DPF几乎所有神经元中都表达IGF - I，其数量随年龄减少。神经分泌性IGF - I免疫反应性轴突最早在17 DPF左右出现在神经垂体中。腺垂体的内分泌细胞在28 DPF时表现出IGF - I mRNA，在40 DPF时表现出IGF - I免疫反应性。因此，IGF - I早期（4 - 5 DPF）出现，首先出现在肝脏中，肝脏是内分泌IGF - I的主要来源，然后出现在参与生长或代谢的器官中。IGF - I的表达在发育过程中比在幼年和成年期更为明显。因此，局部IGF - I似乎在早期生长、代谢和器官发生中具有很高的功能影响。
