Histochemical studies suggest the presence of acid mucopolysaccharides in a number of ocular tissues.1-4 Sialic acids have been found in the aqueous and vitreous humors.5 In order to characterize the glycoproteins of other ocular tissues, analyses for sialic acids were made in different parts of the human eye.
Normal human eyes obtained at autopsy were provided by the eye bank. The anterior chamber was tapped first to collect the aqueous humor. The cornea was excised, and both epithelial and endothelial surfaces were scraped off. The lens was gently extracted, and its capsule was stripped off. The vitreous was collected in 2 portions: the more liquid anterior part and more viscous posterior fraction. The retina was stripped off the choroid and carefully cleared of adherent vitreous.
Each tissue was homogenized separately and heated with 0.1 N H2SO4 at 80 C for 1 hour. The sialic acids
HADDAD HM, BECKER B. Distribution of Sialic Acids in the Human Eye. Arch Ophthalmol. 1961;65(4):563-564. doi:10.1001/archopht.1961.01840020565019