2011 Volume 64 Issue 2 Pages 91-98
Insulin has a well-known regulatory effect on lipolysis. Although many insulin injection studies have been conducted on rats, to date, none have shown that insulin induces visceral fat obesity. The present study was conducted to validate a new animal model of visceral fat obesity induced by the chronic administration of insulin. Female rats were injected subcutaneously with insulin at a dose of 0 (0 I), 8 (8 I), 16 (16 I), or 32 (32 I) IU/kg BW/day for 12 weeks. The survival rate (29%) of rats that received 32 I was significantly decreased in comparison with those that received the 0 I, 8 I, and 16 I (100%). Body weight and the food consumption increased along with insulin doses and the body protein ratio in the 8 I group was increased significantly, compared with that in the 0 I and 16 I groups. The total visceral fat mass and body fat ratio in the 16 I group were also increased significantly in comparison, with that in the 0 I and 8 I groups. These results demonstrate that chronic administration of insulin at a dose of 16 IU/kg BW/day induced visceral fat obesity, thus showing validating this, new animal model of visceral fat obesity induced by insulin.
