Behavioural neuroscienceEnvironmental enrichment selectively increases glutamatergic responses in layer II/III of the auditory cortex of the rat
Section snippets
Environmental conditions
Twenty-three control and 27 EE-raised Sprague–Dawley rats were used in this study. All rats were housed with their mothers and littermates until they reached an age of 21 days. They were then randomly separated and placed into either enriched or standard housing conditions. Rats were given a code of colored tail stripes in order to preserve their housing condition’s confidentiality from experimenters and avoid any unintentional bias. All rats were provided with food and water ad libitum. A
AMPAR-mediated currents in layer II/III
Since EE increases 3H AMPA binding in the hippocampus (Foster et al., 1996) and has been suggested to enhance glutamatergic activity (Foster and Dumas, 2001), we first measured the amplitude of electrically evoked EPSCs in visually identified neurons from layer II/III of the auditory cortex. A paired pulse protocol was applied with an interpulse delay varying between 20 and 1000 ms, for evaluating possible presynaptic differences between EE and the control group. In order to avoid a possible
Discussion
The influence of the environment on animal behavior has long been documented. Several anatomical and physiological studies have clearly demonstrated an involvement of the hippocampus and related structures (Green and Greenough 1986, Foster et al 2000, Sharp et al 1985, Faherty et al 2003, Foster and Dumas 2001). Recently more attention has been focused on how EE affects other brain areas, including the neocortex (Nithianantharajah et al., 2004). In particular, large anatomical rearrangements of
Acknowledgments
J.A.N. performed most of the patch-clamp experiments, analyzed and elaborated data and figures, and contributed to writing the final version of the manuscript, V.P.J. raised the EE animals and contributed to the discussion, H.S. recorded part of the mEPSC and of the APV experiments, L.D. wrote and ran the MatLab program using literature and original data, M.P.K. contributed to the original idea, to the design of the experiments and to the final version of the manuscript, M.A. contributed to the
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