Figure 5: Leptin signaling in cultured rat pineal gland. The glands were challenged with leptin (Lep 1 nM) alone and in association with norepinephrine (NE 1 μM). Immunoblotting (IB) was performed against STAT3, a downstream protein of leptin signaling. α Tubulin is showed as internal control; values are expressed as arbitrary units. One-way ANOVA, followed by Bonferroni’s post hoc test. versus control. glands/group and each experiment was repeated 3 times.