Acide sialique dans les larmes humaines

Abstract

N-Acetylneuraminic acid has been identified in human tears; other accompanying sialic acids have not been found. N-Acetylneuraminic acid has not been found free, but found. A remarkable release is easily produced by hydrolysis with 0.1 N HCl or 0.1 N H₂SO₄ at 80° and with neuraminidase (sialidase) (N-acetylneuraminate glycohydrolase, EC 3.2.1.18) at pH 5.5 and 37°, after about 45 min.

Paper electrophoresis shows its main distribution in a fraction of the pherogram with a mobility of −3.8·10⁻⁵ cm² sec⁻¹ V⁻¹ which would correspond to the α-seroglobulins.

The mean concentration in tears is determined, as well as that of hexoses and hexosamines, and a discussion is made about its biochemical signification.