Figure 1. Effect of central (intracerebroventricular∶ICV) or peripheral (subcutaneous∶SQ) leptin treatment on food intake, weight loss, and serum insulin levels in ob/ob mice.

Leptin deficient, ob/ob mice were continuously administered with leptin over 12-days using central or peripheral route of administration. Both types of leptin infusion significantly decrease food intake, weight, and serum insulin levels, as compared to their respective controls. The weight loss caused by central treatment is significantly greater than the peripheral treatment. Also, the decrease in the insulin level was more in the central group as compared to the peripheral group. VEH_SQ: vehicle subcutaneous treatment, LEP_SQ: leptin subcutaneous treatment, VEH_ICV: vehicle intracerebroventricular treatment, LEP_ICV: leptin intracerebroventricular treatment. Values are mean ± SEM; n = 9 Veh_SQ, n = 10 Lep_SQ, n = 9 Veh_ICV and n = 4 Lep_ICV; *P<0.05 leptin vs respective vehicle, † p<0.05 Lep_ICV vs Lep_SQ.