The EPSP-spike (E-S) component of long-term potentiation in the rat hippocampal slice is modulated by GABAergic but not cholinergic mechanisms
1989; Elsevier BV; Volume: 104; Issue: 1-2 Linguagem: Inglês
10.1016/0304-3940(89)90329-7
ISSN1872-7972
AutoresLaura E. Chavez-Noriega, T.V.P. Bliss, J. V. Halliwell,
Tópico(s)Nicotinic Acetylcholine Receptors Study
ResumoLong-term potentiation of synaptic efficacy (LTP) can be shown to consist of two components: a synaptic and an excitatory postsynaptic potential (EPSP)-spike (E-S) component. The E-S component is expressed as a leftward shift in the curve relating population spike amplitude as a function of EPSP slope. The participation of cholinergic and GABAergic processes in E-S potentiation was studied in field CA1 of rat hippocampal slices. Atropine, a muscarinic antagonist, did not prevent tetanus-induced E-S potentiation. The cholinergic agonist carbachol and the GABAA antagonist picrotoxin produced a leftward shift in the E-S relation; picrotoxin, but not carbachol, prevented the expression of tetanus-induced E-S potentiation. These observations indicate that an increase in the ratio of evoked excitation to inhibition and/or a reduction in tonic inhibition mediated by the activation of GABAA receptors contribute to E-S potentiation produced by high-frequency stimulation.
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