@entity8743 modifies spontaneous inhibitory and excitatory synaptic transmission in XXXX somatosensory cortex.

@entity410 @entity308 @entity8743 @entity302 @entity35
Gap junction (GJ) coupling between neocortical GABAergic interneurons plays a critical role in the synchronization of activity in cortical networks in physiological and pathophysiological states, e.g., @entity410 . Past studies have shown that GJ blockers exert anticonvulsant actions in both in vivo and in vitro models of @entity302 . However, the precise mechanisms underlying these antiepileptic effects have not been fully elucidated. This is due, in part, to a lack of information of the influence of GJ blockade on network activity in the absence of convulsant agents or enhanced neuronal excitation. One key question is whether GJ blockers act on excitatory or inhibitory systems, or both. To address this issue, we examined the effects of the GJ blocker @entity8743 (CarbX, 150 microM) on spontaneous inhibitory postsynaptic currents (sIPSCs) and excitatory postsynaptic currents (sEPSCs) in acute slices of @entity35 somatosensory cortex. Results showed that CarbX decreased the amplitude and frequency of sIPSCs by 30.2% and 25.7%, respectively. CarbX increased the mean frequency of sEPSCs by 24.1%, but had no effect on sEPSC amplitude. During blockade of GABAA-mediated events with picrotoxin (20 microM), CarbX induced only a small increase in sEPSC frequency that was not statistically different from control, indicating CarbX enhancement of sEPECs was secondary to the @entity308 of synaptic inhibition. These findings suggest that in neocortex, blockade of GJs leads to an increase in spontaneous excitation by uncoupling GABAergic interneurons, and that electronic communication between inhibitory cells plays a significant role in regulating tonic synaptic excitation.
