13-P028 Insulin like growth factor-1 concentrations in the cerebrospinal fluid during chick embryonic development

The insulin like growth factors (IGFs) first appeared early in phylogeny about 600 million years ago and have increased in number through gene duplication. In mammals IGFs express in all tissues and are found in many biological fluids. IGF-1 has an important role during central nervous system (CNS) development. IGF-1 promotes differentiation, proliferation and prevents apoptosis of neuronal and brain derived cells. In this study CSF was obtained from the lateral ventricle by puncture using micromanipulation. IGF-1 concentration in CSF samples from chick on embryonic days 8 to 21 (E8–E21) were measured. We have used Western blot and enzyme linked immunosorbent assay (ELISA) to study IGF-1 expression and concentrations. It was shown that IGF-1 levels in the CSF decreased from days E8 to E14. There was a rapid increase in IGF-1 contents on days E15 to E16, after that the concentrations decreased from days E17 to E21. Days E15 to E16 coincide with the onset of neuron proliferation, migration and organization of the cytoarchetecture of the developing chick cortex. Thereafter the IGF-1 concentration decreases until hatching. Since CSF is in contact with cerebral cortical germinal epithelium, changes in the IGF-1 concentration in the CSF might affect on the activity of germinal neuroepithelium and IGF-1 may also be involved in the cerebral cortical development.