Myocardial Infarction-Prone Watanabe Heritable Hyperlipidemic Rabbits with Mesenteric Fat Accumulation Are a Novel Animal Model for Metabolic Syndrome

Abstract

Objectives: To examine whether the myocardial infarction-prone Watanabe heritable hyperlipidemic (WHHLMI) rabbit with visceral fat accumulation is a new animal model for human metabolic syndrome, we examined the relationship between mesenteric fat accumulation and insulin resistance, hyperlipidemia and atherosclerosis. Methods: Glucose tolerance tests were performed using adult (11- to 15-month-old) and middle-aged (17- to 21-month-old) WHHLMI rabbits fed standard chow restrictedly. In addition, lipoprotein lipid levels, serum C-reactive protein (CRP) levels, mesenteric fat weight and physical and physiological parameters were measured. Mesenteric fat was stained immunohistochemically. Results: The mesenteric adipose tissue was positive for monoclonal antibodies against macrophages, C-reactive protein and monocyte chemoattractant protein. In adult rabbits, mesenteric fat correlated to aortic lesion area, insulin resistance, fasting immunoreactive insulin, serum CRP, abdominal circumference and body weight. In middle-aged rabbits, mesenteric fat correlated to lipoprotein lipid levels in addition to the parameters showing a significant correlation in adult rabbits, excluding aortic lesion area. Conclusions: The WHHLMI rabbit with visceral fat accumulation is a new animal model for metabolic syndrome.