Long-term potentiation at excitatory amino acid synapses on ... : NeuroReport (original) (raw)
Neurophsiology
Long-term potentiation at excitatory amino acid synapses on midbrain dopamine neurons
Overton, Paul G.1; Richards, Christopher D.1,3; Berry, Michael S.2; Clark, David1
1Neuropsychopharmacology Laboratory, Department of Psychology,
2School of Biological Sciences, University of Wales Swansea, Singleton Park, Swansea SA2 8PP, UK.
3Corresponding Author: Christopher D. Richards
ACKNOWLEDGEMENTS: This work was supported by grants from the Medical Research Council (G9629658N) and the Biotechnology and Biological Sciences Research Council (58/S09474).
Received 15 October 1998; accepted 16 November 1998
Abstract
Evidence suggests that a process analogous to long-term potentiation (LTP) may underlie the enhanced behavioural responses attending chronic administration of amphetamine and cocaine in animals (behavioural sensitization). Augmented excitatory amino acid (EAA)-mediated transmission at the level of midbrain dopamine neurons has been implicated as a change critical to the development of sensitization. Here we provide an initial demonstration that EAA synapses on dopamine neurons can undergo plasticity. Tetanic stimulation of the subthalamic nucleus induced a long-lasting increase (39.2 ± 10.4%) in the amplitude of excitatory post-synaptic potentials recorded in dopamine neurons of the substantia nigra. This LTP, which did not occur in the presence of NMDA antagonists, may constitute the mechanism that lies at the heart of sensitization.
© 1999 Lippincott Williams & Wilkins, Inc.