Depression of excitatory synaptic input in rat striatal neurons.
Intracellular recording of rat striatal neurons was performed in vitro to investigate posttetanic changes in the excitatory post-synaptic potential (EPSP) elicited by stimulation of the corpus callosum. Tetanic stimulation induced posttetanic potentiation (PTP) in 11 of 12 cells. The PTP decayed in 1-5 min and was followed by either a short or long duration depression of the EPSP in 10 of 12 neurons. The remaining two neurons examined showed a slight enhancement of the EPSP that lasted for 30 min after the tetanus. The group of cells demonstrating short-duration depression (n = 3) were characterized by a decay of the depression to the control level by 15-20 min post-tetanus. The EPSP in the remaining cells showing depression (n = 7) showed a maintained depression for the entire recording session. Blockade of GABAA receptors with bicuculline (30 microM) or NMDA receptors with APV (50 microM) did not effect the induction of long-lasting depression of the striatal EPSP. The data indicates that the corticostriatal pathway can undergo enduring forms of use-dependent synaptic plasticity. This type of synaptic modification may participate in the refinement of movement and contribute to striatal related learning and memory.
Ethel Percy Andrus Gerontology Center, USC Program in Neurosciences, University of Southern California, Los Angeles 90089-0191.
J P
JP
Walsh
D000818:Animals; D003337:Corpus Callosum; D003342:Corpus Striatum / Q000473:pathology / Q000503:physiopathology*; D005071:Evoked Potentials / Q000502:physiology; D066298:In Vitro Techniques; D008297:Male; D008564:Membrane Potentials / Q000502:physiology; D009473:Neuronal Plasticity / Q000502:physiology*; D009474:Neurons / Q000502:physiology*; D051381:Rats; D011916:Rats, Inbred F344; D013569:Synapses / Q000502:physiology*; D013746:Tetany / Q000503:physiopathology*