title: [Evidence of the recycling of vesicle membranes by means of morphometric measurement of the vesicle density (author's transl)].
abstract: Quantitative-electron microscopic investigations have been performed on large morphologically mixed synapses in the oculomotor nucleus of the trout with the aim to get some hints at recycling processes of vesicle membranes. For this reason vesicle density of the presynaptic area and number of vesicle attachment sites of the presynaptic membrane of the active zones within these mixed contacts have been estimated in two different experimental groups. Furthermore, vesicle density near the unmyelinated axolemma of the axon terminal has been measured in both groups. The results obtained support the view that a recycling of vesicle membranes occurs in morphologically mixed synapses, probably also over the axolemma of the so-called extended extracellular spaces, which are interrupting the contact area between the two neuronal elements. The question of a recycling of gap-junction-vesicles has not been answered.
mesh_terms: D000818:Animals; D005260:Female; D008297:Male; D008854:Microscopy, Electron; D008959:Models, Neurological; D009802:Oculomotor Nerve / Q000648:ultrastructure; D017981:Receptors, Neurotransmitter / Q000648:ultrastructure; D013569:Synapses / Q000648:ultrastructure; D013570:Synaptic Membranes / Q000648:ultrastructure; D013572:Synaptic Vesicles / Q000648:ultrastructure*; D014337:Trout / Q000033:anatomy & histology
chemical_list: D017981:Receptors, Neurotransmitter
vernacular_title: Beitrag zum Nachweis des Recycling von Vesikelmembranen mittels morphometrischer Bestimmung der Vesikeldichte.