Figure 2.

For intact cycling (n = 5) or postpartum (n = 6) female rats (Experiment 1), in vivo DA assessments before and during restricted and unrestricted access to pup and food stimuli. A, Basal DA level data (mean ± SEM) represent the average DA concentration of 3 samples collected before any stimuli exposure. Postpartum females had decreased basal DA concentrations compared with their cycling controls: ^ap < 0.05, parity difference. B, After basal collection, the time course for in vivo DA responses relative to basal DA concentrations (mean ± SEM percentage of basal concentration) during restricted access to pups and food (counterbalanced); and unrestricted access to pups, then food.