EN
In adult mice, whiskers stimulation paired with an electrical shock to the tail induces expansion of the cortical representation of stimulated vibrissae and enhances inhibitory interactions within the “trained” barrels. In present experiments we investigated whether such simple associative learning paradigm induced also changes in the neuronal excitability. We prepared brain slices through the barrel cortex and performed whole-cell recordings from visually identifi ed layer IV neurons. Our results showed that excitatory cells located in layer IV of the cortical representation of the “trained” row B of vibrissae had higher frequency of spikes recorded at threshold potential, as compared to both neurons from “untrained” barrel D and to cells from control animals. Additionally, cells within the “trained” barrels displayed bigger gain in the input-output function and decrease in the activation of BK channels responsible for the fast afterhyperpolarisation, which suggests the source for their enhanced intrinsic excitability. The increased excitability of cells within the “trained” barrels may express their homeostatic plasticity which parallels enhanced inhibitory interactions found previously within layer IV of the cortical representation of the “trained” vibrissae. This may be the way to increase the cortical selectivity of response to sensory input from “trained” whiskers. Supported by the MNiSW grants: N30308131/2682, N40114631/3239, COST/127/2007 and PBZ/MNiSW/07/2006.