Objective   To study the change of obesity related index in diet-induced obesity-resistant(DIO-R) rats and diet-induced obesity(DIO) rats.

  Methods   Fifty male Sprague-dawley(SD) rats were randomly divided into control group and high-fat group and they were fed with basic diet and high-fat diet respectively for 13 weeks.DIO-R and DIO rats were selected according to their body weight, then the intake of total calorie and body fat contents, the level of blood glucose, blood fat and serum leptin were determined.

  Results   The intake of total calorie in the first 5 weeks was not significantly different between DIO-R and DIO rats(P > 0.05), but at the end of the experiment, the intake of total calorie of DIO-R rats was significantly lower than those of DIO rats(P < 0.05).The body fat contents, blood glucose, blood fat, TG and CHO of DIO-R rats were lower than those of DIO rats(P < 0.05), while there was no significant difference between DIO-R and DIO rats in the level of HDL-C(P > 0.05).The level of serum leptin of rats in high-fat diet group increased compared with the rat in basic diet group, but there was no significant difference between DIO-R and DIO rats(P > 0.05).

  Conclusion   High fat diets can induce SD rat to develop obesity and obesity-resistance.An increase in serum leptin may play a part of role in resisting diet-induced obesity of rats.