Localization of concanavalin A--binding sites on neuroepithelial cells in early newt's neurula after treatment with noradrenalin.

The concanavalin A (Con A)--binding sites on the cell surface of newt's neural plate and groove in norm and following treatment with noradrenaline (NA) were examined ultrastructurally. The changes in the distribution of Con A--binding sites as well as structural changes of endocytic vacuoles in experimental conditions were described. The present results suggest that the differences in the Con A--binding were caused by receptor interaction of the plasma membrane glycoconjugates and the applied neurotransmitter.