Fig. 2.

Nociceptive responses of adult sexually naïve male mice that were pre-exposed for 1 min to the urine odors of either a sexually receptive intact CD-1-female (intact female) or an ovariectomized female (OVX) and then exposed for 1 min to predator (cat) odor. Responses of mice receiving no female odor exposure (no female) are also given. Nociceptive sensitivity, as measured by the latency of response to a 50 °C thermal surface, was determined before any odor exposures (baseline), after exposure to a female (post-female) and after exposure to the predator odor (post-predator). Stars (*) indicate a significant (p<0.05) decrease in predator odor induced analgesia. N=10 in all cases. Vertical lines denote a standard error of the mean.