Figure 3.

(panels A and C). Acquisition by male mice of a conditioned place preference (CPP) for a chamber in which they previously received estrous female urine (EFU) on the nose and were exposed to soiled estrous female bedding (SEFB). Control males given saline on the nose (saline) and exposed to clean bedding (CB) acquired no CPP. (panels B and D) Separate lesions of the main olfactory epithelium (MOEx) or of the accessory olfactory bulb (AOBx), like sham surgical manipulations of these structures (MOE Sham; AOB Sham; AOB MOE Sham), failed to block the ability of male mice to acquire a CPP to EFU-SEFB. Combined lesions of the AOB and MOE (AOBx MOEx) blocked males’ acquisition of a CPP to EFU-SEFB. Data in the top panels (A, B) are expressed as time (in seconds) spent in the initially non-preferred chamber of the apparatus whereas data in lower panels (C, D) are expressed as preference ratios, defined as the number of seconds spent in the initially non-preferred chamber divided by the time spent in both chambers (mean +/− SEM). For each treatment group of males, time and preference ratio values are shown for the pre-conditioning and for the post-conditioning tests. *p < 0.05, 2-tailed, within-groups t test comparisons of values in the post- vs. pre-conditioning tests. The number (N) of subjects in each group is shown beneath each pair of bars.