胰岛素抵抗高血压大鼠中交感神经系统的研究  

Evaluation of Sympathetic Nervous System in Insulin-resistant Hypertensive Rats

作　　者：李忠艳[1] 李长育[1] 李传勋[2] 花丽艳[1] 李淑芬[1] 

机构地区：[1]大连医科大学附属第二医院心内科 [2]大连医科大学药理学教研室,辽宁省大连市116023

出　　处：《高血压杂志》2000年第2期159-161,共3页Chinese Journal of Hypertension

摘　　要：目的 :从交感神经系统 (SNS)角度探讨胰岛素抵抗 (IR)时高血压及左室肥厚 (L VH)形成的可能机制。方法 :以高蔗糖饲料喂养 8周形成的胰岛素抵抗高血压大鼠(IRHR) (n=13)和正常对照 SD大鼠 (n=10 )为研究对象 ,用荧光测定法测定了其循环和心肌组织去甲肾上腺素 (NE)、多巴胺 (DA)水平的变化 ,并了解其 L VH情况。结果 :IRHR组血压明显高于对照组 ,收缩压、舒张压分别较对照组增高 38mm Hg和 30 mm Hg。 IRHR组血清胰岛素 (Ins)、甘油三酯、左室相对重量均明显高于对照组 (P<0 .0 1) ;其胰岛素敏感性指数、血清高密度脂蛋白明显降低 (P<0 .0 1) ;其血清 NE、DA较对照组增高 (P<0 .0 5 ) ;心肌组织 NE、DA水平降低 (P<0 .0 5 )。光镜及电镜观察发现其左室心肌细胞明显肥大、间质胶原纤维明显增多。结论 :高蔗糖饲料喂养 SD大鼠可以形成胰岛素抵抗和高血压 ,并有脂质代谢紊乱 ,其高血压的形成可能与 IR时的代偿性高胰岛素血症 (HIS)有关。 IRHR的体内 SNS活性增强 ,且与 HIS相关。其 L VH的形成除与血压升高、Ins的直接促增殖作用有关外 ,还可能与 HIS引起的循环及心肌组织Objective:To study the mechanisms by which insulin resistance induces hypertension and left ventricular hypertrophy in related to sympathetic nervous system(SNS). Methods:The insulin resistant hypertensive rats(IRHR) model( n =13) was reproduced by feeding Sprague Dawley(SD) rats for 8 weeks on a high sucrose chow, containing(as percent of calories) 75% sugar. Normal diet SD rats( n =10)were used as a control group. The elements of SNS in plasma and myocardiac tissue were measured by spectrophotofluorometry. Left ventricular relative mass(LVSW/BW) and morphological changes was investigated. Results:(1)Blood pressure(BP) in IRHR was higher than in control group with SBP and DBP of 38 mmHg and 30 mmHg higher respectively. Serum insulin(Ins),C peptide, triglyceride, left ventricular relative mass were higher in IRHR than those in control group(all P< 0 01).Serum high density lipoprotein(HDL C) and insulin sensitive index(ISI) were lower in IRHR (both P< 0 01).(2)The level of serum norepinephrine(NE) and dopamine(DA) were increased, NE、DA in myocardium were decreased in IRHR(all P< 0 05).(3) Myocardial cellular hypertrophy and increased interstitial collagenous fibers were found in IRHR by optical microscopy and electronmicrograph. Conclusions:(1)High sucrose feeding can induce insulin resistance,hypertension and dyslipidemia in the SD rats. Hypertension may be caused by insulin resistance and compensatory hyperinsulinemia.(2)Hyperinsulinemia may activate SNS to increase NE、DA in serum and decrease these sympathetic amines in myocardiac tissue. (3)Significant myocardial cellular hypertrophy and increased interstitial collagenous fibers were found in IRHR. The formation of left ventricular hypertrophy in IRHR may be related to high blood pressure,hyperinsuliemia and overactivated SNS.

关 键 词：高血压 胰岛素抵抗 高胰岛素血症 左室肥厚 

分 类 号：R544.1[医药卫生—心血管疾病]