Effect of infralimbic picrotoxin infusions on the densities of Fos-IR cells in the ipsilateral Ln, BLnM, BLnP, CeL and CeM of the amygdala. No significant changes of densities of Fos-IR nuclei were detected ipsilaterally in any of the regions examined. In both the picrotoxin- and the vehicle-treated groups, densities of Fos-IR nuclei showed a tendency to be higher in the parvocellular subregion of the BLnP as compared with the BLnM and in the central Ln as compared with the CeM. Ln, lateral nucleus; BLnM, basolateral nucleus, magno-cellular; BLnP, basolateral nucleus, parvocellular.