Bezerra R M, Ueno M, Silva M S, Tavares D Q, Carvalho C R, Saad M J, Gontijo J A
Departamento de Planejamento Alimentar e Nutrição, Faculdade de Economia e Administração, Universidade Estadual de Campinas, Campinas, SP, Brasil.
Braz J Med Biol Res. 2001 Sep;34(9):1155-60. doi: 10.1590/s0100-879x2001000900008.
Rats fed a high-fructose diet represent an animal model for insulin resistance and hypertension. We recently showed that a high-fructose diet containing vegetable oil but a normal sodium/potassium ratio induced mild insulin resistance with decreased insulin receptor substrate-1 tyrosine phosphorylation in the liver and muscle of normal rats. In the present study, we examined the mean blood pressure, serum lipid levels and insulin sensitivity by estimating in vivo insulin activity using the 15-min intravenous insulin tolerance test (ITT, 0.5 ml of 6 microg insulin, iv) followed by calculation of the rate constant for plasma glucose disappearance (Kitt) in male Wistar-Hannover rats (110-130 g) randomly divided into four diet groups: control, 1:3 sodium/potassium ratio (R Na:K) diet (C 1:3 R Na:K); control, 1:1 sodium/potassium ratio diet (CNa 1:1 R Na:K); high-fructose, 1:3 sodium/potassium ratio diet (F 1:3 R Na:K), and high-fructose, 1:1 sodium/potassium ratio diet (FNa 1:1 R Na:K) for 28 days. The change in R Na:K for the control and high-fructose diets had no effect on insulin sensitivity measured by ITT. In contrast, the 1:1 R Na:K increased blood pressure in rats receiving the control and high-fructose diets from 117 +/- 3 and 118 +/- 3 mmHg to 141 +/- 4 and 132 +/- 4 mmHg (P < 0.05), respectively. Triacylglycerol levels were higher in both groups treated with a high-fructose diet when compared to controls (C 1:3 R Na:K: 1.2 +/- 0.1 mmol/l vs F 1:3 R Na:K: 2.3 +/- 0.4 mmol/l and CNa 1:1 R Na:K: 1.2 +/- 0.2 mmol/l vs FNa 1:1 R Na:K: 2.6 +/- 0.4 mmol/l, P < 0.05). These data suggest that fructose alone does not induce hyperinsulinemia or hypertension in rats fed a normal R Na:K diet, whereas an elevation of sodium in the diet may contribute to the elevated blood pressure in this animal model.
喂食高果糖饮食的大鼠是胰岛素抵抗和高血压的动物模型。我们最近发现，含有植物油但钠/钾比例正常的高果糖饮食会诱导正常大鼠肝脏和肌肉出现轻度胰岛素抵抗，并伴有胰岛素受体底物-1酪氨酸磷酸化水平降低。在本研究中，我们通过15分钟静脉胰岛素耐量试验（ITT，静脉注射0.5毫升6微克胰岛素）评估体内胰岛素活性，随后计算血浆葡萄糖消失速率常数（Kitt），以此来检测雄性Wistar-Hannover大鼠（110-130克）的平均血压、血脂水平和胰岛素敏感性。这些大鼠被随机分为四个饮食组：对照组、1:3钠/钾比例（R Na:K）饮食组（C 1:3 R Na:K）；对照组、1:
