高蔗糖诱发大鼠胰岛素抵抗和高血压机制实验研究

Experimental Research of Mechanism in Hypertension and Insulin Resistance Induced by High Sucrose Intake in Rats

雄性Wistar大鼠50只分为2组,每组25只。分别以高蔗糖和普通饲料饲养20周,观察血压、血糖、胰岛素、血浆肾素活性、血管紧张素Ⅱ及尿量、尿去甲肾上腺素和尿钠改变至16周。20周行糖耐量试验后处死大鼠测肾脏、骨骼肌及心肌肾素活性和血管紧张素Ⅱ水平。结果表明:试验组血压、血糖、血浆肾素活性和血管紧张素Ⅱ,尿量及尿去甲肾上腺素自4周,胰岛素自12周开始升高至16周,尿钠自4周开始降低至16周。16周测血钠明显升高。糖耐量试验及同期测胰岛素,基础血糖值和注射糖后30分血糖值和基础胰岛素值与对照组无明显差异。90分血糖及30、90分胰岛素值明显升高,90分测定的血浆肾素活性,血管紧张素Ⅱ也明显升高。肾脏的肾素活性和血管紧张素Ⅱ高于对照组,骨骼肌和心肌差异无显著性。结论:高蔗糖诱发大鼠高血压和胰岛素抵抗,发生机制是通过肾素-血管紧张素系统活性增加实现的。胰岛素抵抗对血压升高无直接作用。

Fifty male Wistar rats were divided into two groups,25 rats were fed with high sucrose food,and the others with standard rat chew for 20 weeks,to observe the changes of blood pressure,plasma glucose, insulin, plasma renin activity (PRA) , angiotensin Ⅱ (AT Ⅱ), urinary volume, urinary nore-pinephrine and urinary sodium for 16 weeks. Then intravenous glucose test was performed and the tissue renin activity and angiotensin Ⅱ were investigated. The purpose of the study was to investigate whether the high sucrose intake could induce hypertension and insulin resistance, and its mechanism. After 16 weeks observation,the results of the high sucrose group compared with the controls were;the blood pressure, blood sugar, PR A, AT Ⅱ, urinary volume and norepinephrine were evaluated from 4th week,and insulin from 12th week,to 16th week. The urinary sodium decreased from 4th week up to 16th week in high sucrose group than in controls. The results of the intravenous glucose test at the 20 weeks showed that 90 min blood sugar and 30 and 90 min insulin levels were higher than those in controls. The PRA and AT Ⅱ at the 90 min were also elevated. The renal renin activity and AT II were increased in high sucrose rats but in the muscle and heart there was no difference. Conclusion: the mechanism of hypertension and insulin resistance induced by high scrose feeding are produced through increased renin-angiotensin system activity. Insulin resistance has no direct effect on hypertension development.