FIGURE 4.

Hypothalamic leptin signaling. A, 4-month-old, and B, 6-month-old male Cc1^+/+ and Cc1^−/− mice (n = 3–5 per treatments per genotype) received an i.c.v. injection of vehicle (Veh, open or solid bars) or leptin (Lep, gray- and black-striped bars) 45 min prior to tissue isolation. Coronal sections from the medial hypothalamus were subjected to immunohistochemical analysis with phospho-STAT3. The mean number of stained hypothalamic neurons of the medial hypothalamus is shown as ± S.E. *, p < 0.05 versus vehicle in each mouse group.