Eating behavior and fat transport from the interstine in old and obese rats

OLETF大鼠是一种NIDDM模型，在18周龄时首次表现出来。我们评估了OLETF大鼠肠道淋巴脂质转运的年龄相关变化，并与对照组LETO大鼠进行了比较。在乙烷麻醉下形成肠系膜淋巴瘘的患者体内注入橄榄油。与17周龄以下相比，18-19周龄的OLETF大鼠淋巴甘油三酯转运显著增加，而LETO大鼠的淋巴甘油三酯转运无明显变化。OLETF大鼠的食物限制、运动训练或曲格列酮治疗可阻止与年龄相关的脂质转运增加。OLETF大鼠胆汁中磷脂酰胆碱浓度高于LETO大鼠，但两品系大鼠胆汁中的胆汁酸浓度无明显差异。本研究表明NIDDM可引起肠道脂质转运增加。NIDDM发生后，OLETF大鼠和LETO大鼠的能量消耗日变化不同。饮食限制、运动或曲格列酮的治疗使昼夜轮廓恢复正常。口服二酰甘油增加了人体CCK的释放，但其反应与甘油三酯诱导的没有区别。在CCK-A受体基因敲除小鼠中，观察到它们在高脂肪和高蛋白饮食中形成胆结石。

OLETF rats are a model for NIDDM, which is first manifested at 18 weeks of age. We assessed age-related changes in lymphatic lipid transport in the intestine of OLETF rats and compared them with those of control LETO rats. Olive oil was infused into thterats with a mesenteric lymph fistula, which was created under ethrane anesthesia. A significant increase in lymphatic triglyceride transport in OLETF rats was observed at 18-19 weeks of age, compared with under 17 weeks of age, but no age-related change was observed in LETO rats. Food restriction, exercise training, or troglitazone treatment in OLETF rats prevented the age related increase in lipid transport. Biliary phosphatidylcholine concentration was higher in OLETF rats than in LETO rats, but no difference was seen in bile acid concentrations of the activity of microsomal TG transfer protein between the two strains. This study shows that increased lipid transport in the intestine may occur in NIDDM.The diurnal profile of energy expenditure in OLETF rats was different from LETO rats after NIDDM manifested. Treatments with food restriction, exercise, or troglitazone normalized diurnal profiles.Oral administration of diacylglycerold increased CCK release in humans, but the response was not different from that induced by triglyceride.Gallstone formation was observed when they were raised with high fat and high protein diet in CCK-A receptor knockout mice.