Lectin binding sites in parotid acinar secretory granules of normal and isoproterenol treated rat

Lectin staining patterns in secretory granules of rat parotid gland acinar cell of untreated and isoproterenol-injected animals were examined by elect ron microscopy. We used four lectin-gold complexes: Ulex europaeus agglutin in I (UEA-I), Helix pomatia agglutinin (HPA), wheat germ agglutinin (WGA), Glycine max agglutinin (SBA). Specimens were low temperature embedded in th e hydrophilic Lowicryl K4M resin. The normal acinar cells produced glycocon jugates which were positive for all of the lectins used and with a characte ristic topographic distribution in relation to the morphological type of gr anule. The cells of isoproterenol-treated rat showed marked ultrastructural changes in the size and structure of granules; significant changes in lect in binding sites in the granules were also observed.