title: Repeated electroconvulsive stimulation impairs long-term depression in the neostriatum.
abstract: BACKGROUND
  Increasing and consistent findings of structural and functional abnormalities in patients with mood disorders demonstrate a clear involvement of the neostriatum. Therefore, the beneficial effect of electroconvulsive stimulation (ECS) treatment of acute state of mood disorder may relate to changes in striatal synaptic plasticity.
  
  
  METHODS
  We studied the effect of ECS treatment on the reported long-term depression (LTD) of synaptic excitatory afferents to striatal medium spiny neurons. Stimulation of the white matter between the cortex and the striatum elicited excitatory postsynaptic potentials (EPSPs) in medium spiny neurons in rat corticostriatal slices while recording using the whole-cell patch-clamp technique.
  
  
  RESULTS
  The EPSPs evoked in striatal neurons undergo LTD with repeated stimulation trains, and LTD of this pathway is impaired in rats after ECS treatment for 1 week, similar to what is reported in chronic lithium treatment. Electroconvulsive stimulation did not affect intrinsic membrane properties or the occurrence of spontaneous EPSCs. Dose-dependent inhibition of the EPSPs by a nonselective agonist of metabotropic glutamate receptor did not change in rats after ECS treatment.
  
  
  CONCLUSIONS
  Our data suggest that the effectiveness of electroconvulsive therapy in mood disorders may be a consequence of LTD impairment of excitatory cortical afferents to striatal projecting neurons.
authors.affiliation: Clinica Psichiatrica II Universitá di Roma la Sapienza (MDM, RT, PG), Rome, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: De Murtas
authors.forename: Roberto
authors.initials: R
authors.lastname: Tatarelli
authors.forename: Paolo
authors.initials: P
authors.lastname: Girardi
authors.forename: Stefano
authors.initials: S
authors.lastname: Vicini
mesh_terms: D000818:Animals; D004565:Electroconvulsive Therapy; D004830:Epilepsy, Tonic-Clonic / Q000378:metabolism* / Q000628:therapy*; D019706:Excitatory Postsynaptic Potentials; D036881:Long-Term Synaptic Depression / Q000502:physiology; D017072:Neostriatum / Q000166:cytology / Q000378:metabolism*; D009473:Neuronal Plasticity / Q000502:physiology; D009474:Neurons / Q000378:metabolism*; D018408:Patch-Clamp Techniques; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D018094:Receptors, Metabotropic Glutamate / Q000378:metabolism
chemical_list: D018094:Receptors, Metabotropic Glutamate