ELECTRON CYTOCHEMICAL STUDY OF CARBOHYDRATE COMPONENTS IN CULTURED NERVE AND GLIAL-CELLS OF THE SNAIL HELIX-POMATIA

1. A variety of colloidal gold-labelled lectins with different sugar s pecificities to determine whether different nerve and glial cells of t he snail Helix pomatia cultured in vitro, can be distinguished by the carbohydrates that they express was screened. The analysis of lectin b inding has shown substantial differences in the carbohydrate pattern b etween nerve and glial cells and between the soma of monoaminergic and peptidergic neurons. 2. The surface of monoaminergic and peptidergic neurons contains N-acetylglucosamine and N-acetyllactosamine determina nts, and does not exhibit neuraminic acid and complex branched N-glyco syl chains. Moreover, N-acetylgalactosamine can be detected on peptide rgic neuron membranes only. 3. N-Acetylglucosamine residues are not pr esent on the surface of the glial cells, and the density of the N-acet yllactosamine and/or terminal beta-galactose residues is much higher h ere than on the surface of the nerve cells. 4. These results suggest t hat nerve cells in the snail brain can be distinguished from glial cel ls by the presence of a cell-surface glycoconjugate containing termina l N-acetyl-D-glucosamine residues, whereas peptidergic neurons can be distinguished from monoaminergic neurons by the presence of a surface glycoconjugate containing terminal alpha-linked N-acetyl-D-galactosami ne residues.