Leptin resistance in a polygenic, hyperleptinemic animal model of obesity and NIDDM:: Psammomys obesus

OBJECTIVE: To investigate the effects of leptin administration to Psammomys obesus, a polygenic animal model of obesity and type 2 diabetes mellitus, DESIGN: Longitudinal intervention study utilising three separate leptin treatment protocols lasting 7-14d, MEASUREMENTS: Body weight and food intake were measured daily, body fat and muscle content were estimated by carcass analysis on completion of the study. Blood glucose, plasma insulin, leptin, triglycerides and cholesterol were measured at baseline and twice each week during the study. RESULTS: Relatively high doses of leptin were required to significantly reduce food intake and body fat content in lean Psammomys obesus, but had no discernible effect on their obese littermates. CONCLUSION: As a species, Psammomys obesus appear to be relatively insensitive to the effects of leptin administration, compared with other rodents. Obese Psammomys obesus are leptin resistant relative to their lean littermates.