title: Reduced level of synapsin I protein in the rat striatum after intraventricular administration of proteasome inhibitors: preliminary studies.
abstract: BACKGROUND
  We have recently described changes present in nigrostriatal terminals after intraperitoneal administration of MG-132 and changes that occur in the walls of the rat lateral ventricle after intraventricular administration of MG-132, lactacystin and epoxomicin - different classes of proteasome inhibitors. Substances that inhibit ubiquitin-proteasome system (UPS) activity, are intensively studied due to their potential role as novel therapeutic strategies in the treatment of cancer and ischaemia-reperfusion injury in the brain. The aim of this study is to determine the influence of intraventricular administration of MG-132, lactacystin and epoxomicin on the level in the rat striatum synapsin I - one of the most prominent neuron-specific phosphoproteins in the brain.
  
  
  RESULTS
  Two weeks after administration of studied proteasome inhibitors, substantial reduction (up to 80%) of synapsin I was ob-served in the rat striatum. Because neurons, and especially dopaminergic ones, are sensitive to the depletion of proteasome function, we assume that observed synapsin I decrease may reflect changes in population of striatal neurons and/or nigrostriatal terminals.
  
  
  CONCLUSIONS
  Understanding of cellular mechanisms standing behind our findings needs further studies, and could provide valuable contribution to the discussion on the mechanisms linking UPS inhibition and survival of neurons.
authors.affiliation: Department of Anatomy and Neurobiology, Medical University of Gdansk, Gdansk, Poland. swoj@gumed.edu.pl.
authors.forename: S
authors.initials: S
authors.lastname: Wójcik
authors.forename: J H
authors.initials: JH
authors.lastname: Spodnik
authors.forename: J
authors.initials: J
authors.lastname: Sidor-Kaczmarek
authors.forename: J
authors.initials: J
authors.lastname: Moryś
keywords: MG-132; Western blot; epoxomicin; lactacystin; neuronal nuclear antigen; rat; synapsin I