Figure 6
From: Female mice are more prone to develop an addictive-like phenotype for sugar consumption
Long-term operant self-administration for sugar in male (n = 23) and female (n = 23) mice (Experiment 3a). (A) Number of rewards earned, (C) inactive lever pressing per sessions, during FR1 (15 sessions) and FR4 (29 sessions) schedule of reinforcement. Mean from the last 5 sessions of (B) rewards earned, and (D) inactive lever pressing in males (white circles/bars) and females (grey circles/bars). (A) During the FR1 phase, all mice similarly acquired and maintained stable active lever pressing for sugar and (B) the mean from the last 5 sessions did not differ between male and female mice. (C) Inactive lever pressing was higher in female mice across the 15 FR1 sessions, and (D) the mean of the last 5 sessions showed a significant increase compared to male mice. During the FR4 phase, (A) females earned more rewards and made more responses on the inactive lever (C,D). All data represent mean ± SEM. # indicates P < 0.05 versus male mice.
