Zanchi A, Delacrétaz E, Taleb V, Gaillard R, Jeanrenaud B, Brunner H R, Waeber B
Hypertension Division, University Hospital, Lausanne, Switzerland.
J Hypertens. 1995 Dec;13(12 Pt 1):1463-70.
To examine whether insulin resistance and hypercholesterolaemia in obese Zucker rats are associated with a modification of the mechanical behaviour of a conductance (carotid) artery and with an altered endothelium-dependent response to acetylcholine of a small resistance (mesenteric) artery.
Male obese Zucker rats, 6-8 months old, were compared with age-matched lean heterozygous and control Zucker rats.
The mechanical behaviour of the carotid artery was examined in anaesthetized rats by simultaneously monitoring the internal diameter with an A-mode ultrasonic echo-tracking device and the intra-arterial pressure with a computerized data-acquisition system. Furthermore, histometric measurements of the carotid artery were carried out after death. The response to acetylcholine was examined in vitro with a Mulvany dual myograph on precontracted isolated segments of the third-generation mesenteric artery.
Obese Zucker rats exhibited high plasma insulin and cholesterol levels. Blood pressure was the same in the obese and control animals. There was no hypertrophy or change in the mechanical behaviour of the carotid arterial wall. Heart weight was slightly higher in the obese rats than in the controls, but smaller in relation to body weight. The relaxation to acetylcholine was significantly attenuated in isolated small mesenteric arteries obtained from the obese strain.
Hyperinsulinaemia and hypercholesterolaemia in obese Zucker rats are associated with an abnormal response to acetylcholine in the mesenteric arterioles. This metabolic state does not, however, alter the mechanical behaviour or the geometry of the carotid artery.
研究肥胖型 Zucker 大鼠的胰岛素抵抗和高胆固醇血症是否与传导性（颈动脉）动脉的力学行为改变以及小阻力（肠系膜）动脉对乙酰胆碱的内皮依赖性反应改变有关。
将 6 - 8 月龄的雄性肥胖型 Zucker 大鼠与年龄匹配的瘦杂合子和对照 Zucker 大鼠进行比较。
在麻醉的大鼠中，通过使用 A 型超声回声跟踪装置同时监测内径和计算机化数据采集系统监测动脉内压力，来检查颈动脉的力学行为。此外，在大鼠死后进行颈动脉的组织测量。使用 Mulvany 双肌动描记器在第三代肠系膜动脉的预收缩离体节段上体外检查对乙酰胆碱的反应。
肥胖型 Zucker 大鼠表现出高血浆胰岛素和胆固醇水平。肥胖大鼠和对照动物的血压相同。颈动脉壁的力学行为没有肥大或改变。肥胖大鼠的心脏重量略高于对照组，但相对于体重较小。从肥胖品系获得的离体小肠系膜动脉对乙酰胆碱的舒张作用明显减弱。
肥胖型 Zucker 大鼠的高胰岛素血症和高胆固醇血症与肠系膜小动脉对乙酰胆碱的异常反应有关。然而，这种代谢状态不会改变颈动脉的力学行为或几何形状。
