Abstract
Abstract: :
Purpose: The inner limiting membrane (ILM) and the vitreous body (VB) are major parts of the extracellular matrix of the eye. The present study investigates the synthesis and turnover of the ILM and VB in during chick and human embryonic and post–embryonic eye development. Methods:The abundance of ILM and VB proteins was determined by Western blotting using samples from chick and human VB of different ages. The mRNA expression of the ILM proteins in lens was determined by in situ hybridization and RT–PCR. Results:ILM and VB proteins in chick are synthesized by lens and ciliary body and secreted into the VB. The proteins are most abundant in embryogenic VB, and their concentration sharply declines after hatching. Most ILM and VB proteins were no longer detectable in the adult VB. Similar data were obtained for human eyes. In humans, the drop in ILM and VB protein synthesis occurs during the first 2 years of age. Conclusions: The abundance of ILM and VB proteins in the embryonic VB, their sharp decline at postembryonic stages and their very low abundance in the adult VB show that ILM and VB are assembled during embryogenesis and maintained throughout life with minimum turnover.
Keywords: extracellular matrix • vitreous • retinal development