Lectins are markers of neuronal migration and differentiation in rat brain

The binding of the lectins concanavalin A (Con A), peanut lectin (PNL), Ricinus communis agglutinin I (RCA I), Ulex europaeus agglutinin I (UEA I) and wheat germ agglutinin (WGA) to rat brains at several fetal and neonatal stages of development was evaluated. Cytochemical staining was performed using biotinylated lectins with an avidin-biotin complex with and without neuraminidase digestion. Differential binding to ventricular and intermediate layers, cortical plate and blood capillaries was demonstrated at different stages of development. WGA bound to blood capillaries at all ages, RCA I and PNL + N (PNL after neuraminidase digestion) from gestational day 22 on. During migration RCA I bound to cell fibers, PNL and UEA I to migrating cell bodies. Con A and UEA I stained perikaryonal structures of cortical neurons increasingly during neonatal development. It appears that cytochemical methods utilizing lectins can be used for the investigation of developmental processes of the central nervous system.