EN
Gabaergic interneurons are involved in regulating developmental plasticity of visual, auditory and somatosensory cortices, as well as in learning and memory processes. It has been suggested that age related worsening of brain function and plasticity could be, at least in part, attributed to alterations in gabaergic system. Gabaergic interneurons constitute a heterogeneous cell population classified into groups based on their calcium binding protein content. In the present study, we evaluate with immunohistochemistry technique the effect that aging has on the three of them, namely Parvalbumin (PV)-, Calbindin (CB)- and Calretinin (CR)-expressing neurons, in the somatosensory cortex of young (3 month old) and middleaged (1 year old) mice. We found that the distribution across layers differs between neuron types. PV-positive neurons were observed across the thickness of the cortex, with highest densities in layer IV. CB-positive neurons were much less numerous than the latter, and were observed in layers II/III and V/VI. Layer IV was practically devoid of CB-positive neurons. CR-positive neurons were scarcely distributed across all layers, with lower densities in layers V/VI. We did not observe the effect of age in neither of the neuron type examined. It suggested that age-dependent decline of somatosensory cortex plasticity does not depend on gabaergic neuron loss.