. "The process in which a neuronal cell maintains the organization and the arrangement of proteins at the active zone to ensure the fusion and dock of vesicles and the release of neurotransmitters." . . "maintenance of presynaptic active zone structure" . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .