Russell J C, Koeslag D G, Manickavel V, Amy R M, Dolphin P J
Department of Surgery, University of Alberta, Edmonton, Canada.
Diabetes Res. 1990 Oct;15(2):53-62.
Corpulent rats of the JCR:LA-corpulent strain spontaneously develop atherosclerotic lesions, occlusive thrombi and myocardial lesions. In addition to exhibiting a VLDL hyperlipidemia they are insulin resistant. Young male corpulent rats have significantly impaired rates of clearance of plasma glucose on an intravenous glucose tolerance test in comparison to lean rats (k = 0.94 +/- 0.69 vs 2.06 +/- 0.64 x 10(-2) min-1, p less than 0.01). Food restriction to 60% of the spontaneous intake of lean controls (12 g/day) for 10 days raised the rate of glucose clearance to that of the lean rats (k = 3.01 +/- 0.40 x 10(-2) min-1) and this was highly significant compared to the rate at three months of age (p less than 0.0005). Food restriction significantly lowered the elevated insulin levels of corpulent rats at 3 and 12 months of age. It inhibited, but did not prevent, the development of hyperplasia of the islets of Langerhans. The hypertriglyceridemia was less severe in 12 month old rats (214 +/- 52 vs 282 +/- 19 mg/100 ml while total cholesterol was increased (129 +/- 20 vs 85 +/- 5.5 mg/100 ml). Severe food restriction halved the triglyceride concentration at both 3 and 12 months of age while total cholesterol was unaffected. The food restriction throughout life up to 12 months of age, however, did inhibit the development of advanced myocardial lesions.
LA肥胖品系的肥胖大鼠会自发形成动脉粥样硬化病变、闭塞性血栓和心肌病变。除了表现出极低密度脂蛋白高脂血症外，它们还具有胰岛素抵抗性。与瘦大鼠相比，年轻雄性肥胖大鼠在静脉葡萄糖耐量试验中血浆葡萄糖清除率显著受损（k = 0.94 ± 0.69 vs 2.06 ± 0.64×10⁻² min⁻¹，p < 0.01）。将食物摄入量限制为瘦对照组自发摄入量的60%（12克/天），持续10天，可使葡萄糖清除率提高到瘦大鼠的水平（k = 3.01 ± 0.40×10⁻² min⁻¹），与三个月龄时的清除率相比，这具有高度显著性（p < 0.0005）。食物限制显著降低了3个月和12个月龄肥胖大鼠升高的胰岛素水平。它抑制了，但并未阻止，胰岛增生的发展。12个月龄大鼠的高甘油三酯血症较轻（214 ± 52 vs 282 ± 19 mg/100 ml），而总胆固醇有所增加（129 ± 20 vs 85 ± 5.5 mg/100 ml）。严格的食物限制在3个月和12个月龄时使甘油三酯浓度减半，而总胆固醇不受影响。然而，终生至12个月龄的食物限制确实抑制了晚期心肌病变的发展。
