title: Effects of lamotrigine on human motor cortex plasticity.
abstract: OBJECTIVE
  Besides its use in epilepsy, lamotrigine (LTG) is also effective as mood stabilizer. The pathophysiology of mood disorders may incorporate a dysfunction of neuronal plasticity and animal experiments suggest that mood stabilizers influence induction of long-term potentiation (LTP) and -depression (LTD), two major forms of synaptic plasticity. However, the exact modes of action of LTG and its impact on neuronal plasticity in humans remain unclear.
  
  
  METHODS
  Here, we tested the effects of a single oral dose of LTG (300 mg) on motor cortical plasticity induced by paired associative stimulation (PAS(25)), a protocol that typically induces LTP-like plasticity, in 26 young healthy adults in a placebo-controlled, randomized, double-blind crossover design. We stratified analysis of the LTG effects according to the individual PAS(25) response in the placebo session (14 LTP-responders vs. 12 LTD-responders). Plasticity was indexed by motor evoked potential (MEP) amplitudes recorded before and for 60 min after PAS(25).
  
  
  RESULTS
  LTG resulted in a significant reduction of the LTP-like MEP increase in the LTP-responders and a reduction of the LTD-like MEP decrease in the LTD-responders, with the majority of LTD-responders even showing an MEP increase.
  
  
  CONCLUSIONS
  In summary, LTG differentially modulated cortical plasticity induced by non-invasive brain stimulation in human subjects depending on their individual intrinsic propensity for expressing LTP-like or LTD-like plasticity.
  
  
  CONCLUSIONS
  Findings contribute to our understanding of the anticonvulsant and antidepressant clinical effects of LTG, which have been suggested to occur, at least in part, through downregulation of LTP (epilepsy) and LTD (depressive disorders).
authors: European Neuroscience Institute Göttingen, Göttingen, Germany.
authors: Igor
authors: I
authors: Delvendahl
authors: Hannes
authors: H
authors: Lindemann
authors: Tonio
authors: T
authors: Heidegger
authors: Claus
authors: C
authors: Normann
authors: Ulf
authors: U
authors: Ziemann
authors: Volker
authors: V
authors: Mall
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D000927:Anticonvulsants / Q000494:pharmacology*; D018592:Cross-Over Studies; D003627:Data Interpretation, Statistical; D004311:Double-Blind Method; D004558:Electric Stimulation; D004576:Electromyography; D019054:Evoked Potentials, Motor / Q000187:drug effects; D005260:Female; D006801:Humans; D000077213:Lamotrigine; D017774:Long-Term Potentiation / Q000187:drug effects; D008297:Male; D008475:Median Nerve / Q000502:physiology; D009044:Motor Cortex / Q000187:drug effects*; D018482:Muscle, Skeletal / Q000502:physiology; D009473:Neuronal Plasticity / Q000187:drug effects*; D012016:Reference Values; D050781:Transcranial Magnetic Stimulation; D014227:Triazines / Q000494:pharmacology*; D055815:Young Adult
chemical_list: D000927:Anticonvulsants; D014227:Triazines; D000077213:Lamotrigine