title: Presynaptic elements formed on polylysine-coated beads contain synaptic vesicle antigens.
abstract: Cell cultures of the rat cerebellum were immunostained with antibodies to synaptic vesicle antigens, Synapsin I and SV48. Light microscopic immunocytochemistry showed that the initial appearance of demonstrable SV48 and Synapsin I immunoreactivity occurred at different times. Synapsin I immunostaining, unlike SV48 immunostaining, was first seen at 3 days in vitro as occasional punctate immunofluorescence in neurites, while SV48 immunostaining was first seen at 5 days in vitro. Both SV48 and Synapsin I punctate immunostaining became frequent at 7 days in vitro. Double labelling experiments showed coexistence of the above proteins in punctate swellings and growth cones. Using the electron microscope, either SV48 or Synapsin I immunostaining was demonstrated within presynaptic elements in the neuropil. When cultures were incubated with polylysine-coated beads, both types of immunostaining were found in the vesicle containing presynaptic elements formed on the bead surface. It is concluded that Synapsin I and SV48 are co-localized in the same populations of presynaptic elements, co-localized in some growth cones and found in presynaptic elements on beads.
mesh_terms: D000818:Animals; D001921:Brain / Q000166:cytology; D005455:Fluorescent Antibody Technique; D006651:Histocytochemistry; D008854:Microscopy, Electron; D009419:Nerve Tissue Proteins / Q000032:analysis*; D011107:Polylysine; D051381:Rats; D016704:Synapsins; D013572:Synaptic Vesicles / Q000276:immunology*
chemical_list: D009419:Nerve Tissue Proteins; C050062:SV48; D016704:Synapsins; D011107:Polylysine