Insulin resistance, visceral fat and hypertension

The present study was undertaken to assess the relationship between insulin resistance and visceral fat volume and hypertension in genetically obese diabetic rats (Otsuka Long-Evans Tokushima Fatty (OLETF)) and control rats (Long-Evans Tokushima Otsuka (LETO)). Euglycemic hyperinsulinemic clamp and abdominal computed tomography were performed at the age of 15 and 29 weeks in the rats. Body weight was significantly greater in OLETF than in LETO rats at both ages. A significant relationship (p<0.05) between glucose infusion rate (GIR) and visceral fat volume was obtained in the 15-week-old rats. Although we failed to find a difference in GIR between OLETF and controls in the 15-week-old rats, there was a significant difference in GIR in the 29-week-old rats. There was a significant negative correlation between GIR and systolic blood pressure at the age of 15 weeks, but such a relationship disappeared in the 29-week-old rats. The same phenomenon was also obtained regarding diastolic blood pressure. Thus, insulin resistance may be an important factor in regulating blood pressure, but an unknown factor may also be involved in the development of hypertension.