Intraventricular leptin reduces food intake and body weight of lean rats but not obese zucker rats. - Seeley,R.J.; Van Dijk,G.; Campfield,L.A.; Smity,F.J.; Burn,P.; Neliigan,J.A.; Bell,S.M.; Baskin,D.G.; Woods,S.C.; Schwartz,M.W. (Horm Metab Res, 1996)