Adenosine‐induced inhibition of evoked postsynaptic potentials (PSPs) and epileptiform burst firing in the CA1 subfield of rat hippocampal slices was studied with intracellular recordings in vitro. Adenosine (50 μM) caused a membrane hyperpolarization which was abolished during superfusion with 2 mM Ba2+. The adenosine‐induced inhibition of the PSPs was still evident, although the magnitude of the effect was significanty reduced. Adenosine also reduced Ba2+‐induced burst firing, but less effectively than it did bursts evoked by TEA (5 mM). The results suggest that adenosine inhibits synaptic transmission and epileptiform activity by at least 2 mechanisms: a postsynaptic barium‐sensitive increase in gK and a presynaptic effect independent of this adenosine‐evoked outward potassium conductance. © Wiley‐Liss, Inc.
- Potassium channels
- Presynaptic inhibition
ASJC Scopus subject areas
- Cellular and Molecular Neuroscience