Detrimental effect of olfactory bulbectomy (OBX) in mice on the density of choline acetyltransferase (ChAT)-containing neurons in the forebrain, beneficial effects of the immunization against the p75NTR amino acid residues of 32–46, 86–93, and 147–154, and overgrowing effects of the treatment with 155–164 and 167–176 fragments. The immunoreactive labeling against ChAT in the nucleus basalis magnocellularis on the representative examples (taken from the area marked by a rectangle on B) demonstrates decreased number of the labeled cells after the bulbectomy (c.f., C and D) and their recovery after the immunization against the fragments of 155–164 (E) and 167–176 (F). White horizontal bars in C-F are the scale bars of 50 μm. On A, error bars show 1 SEM; star or plus denote significant differences versus either SO or OBX, respectively (one and two markers are p < 0.05 and 0.01, Mann-Whitney U-test). The brain slice on B was modified from [40].