Figure 1.

Experimental Timeline. Experimental timeline of all three phases of the study. Following a 3 week acclimatization period at Columbia University, mice were nine weeks old at the start of the experiment. Mini-pumps containing increasing quantities of leptin were surgically replaced every two weeks during an 18-week infusion period (Phase 1). Blood was obtained by retro-orbital bleed following a 4-h fast eight days after each mini-pump switch during the 18 weeks of Phase 1 as well as well as 5, 41, and 118 days following removal of the final pump (see black circles).