Figure 2

Murine-p75-saporin injections depleted cholinergic neurones in the MSDB. (A) Extent of the depletion of cholinergic neurones. Photomicrographs of representative sections through the MSDB immunostained for ChAT visualized with DAB from mice infused with (i) saline and (ii) 3.6 μg/μl of murine-p75-saporin (mu-p75-SAP). Scale bar = 100 μm. (B) Quantification of the extent of the cholinergic depletion. Number of ChAT-immunopositive cells in the MSDB following intracerebroventricular infusion of saline (saline) or mu-p75-SAP (lesion) and sacrifice either 24 hours after the end of running wheel exposure (24 hrs lesion) or 4 weeks after the end of running wheel exposure (4 weeks lesion). Data are mean ± sem; * p < 0.05, ** p < 0.01. (C) Selectivity of the cholinergic lesions in the MSDB. Confocal micrographs of double immunofluorescence labelling for ChAT (red) and parvalbumin (green), a marker for GABAergic cells, in representative sections from (i) saline control and (ii) mu-p75-SAP infused mice. Parvalbumin-positive cells remained intact despite of loss of ChAT-positive cells. Scale bar = 100 μm.