Department of Physiological Sciences, Laboratory of Stress, Piracicaba Dental School, University of Campinas, Piracicaba, Sao Paulo, Brazil.
Stress. 2009 Jul;12(4):320-7. doi: 10.1080/10253890802437779.
The aim of this study was to analyze the effects of chronic mild unpredictable stress (CMS) on the vasoconstrictor response and morphology of the thoracic aorta and serum lipid profiles in rats. Male Sprague-Dawley rats were submitted to CMS, which consisted of the application of different stressors for 7 days per week across 3 weeks. The rats were sacrificed 15 days after CMS exposure. CMS induced supersensitivity to the vasoconstrictor effect of phenylephrine in endothelium-intact thoracic aortic rings without changes in aortic rings without endothelium, or pre-incubated with nitric oxide (NO) synthesis inhibitor. Rats submitted to CMS showed hypertrophy of the intima and tunica media of thoracic aorta, increased serum levels of triglycerides, total cholesterol, very low-density lipoprotein cholesterol, low-density lipoprotein cholesterol and atherogenic index, without changes in high-density lipoprotein cholesterol levels, when compared with control rats. These data indicate that CMS induces physiological and morphological changes that may contribute to the development of atherosclerosis by mechanisms related to deficiency in NO production and dyslipidemia.
本研究旨在分析慢性轻度不可预测应激（CMS）对大鼠胸主动脉血管收缩反应和形态以及血清脂质谱的影响。雄性 Sprague-Dawley 大鼠接受 CMS 处理，每周 7 天施加不同的应激源，共 3 周。CMS 暴露后 15 天处死大鼠。CMS 诱导内皮完整的胸主动脉环对苯肾上腺素的血管收缩作用超敏，而对无内皮的主动脉环或预先用一氧化氮（NO）合成抑制剂孵育的主动脉环没有影响。与对照组大鼠相比，接受 CMS 的大鼠表现出胸主动脉内膜和中膜的肥大，血清甘油三酯、总胆固醇、极低密度脂蛋白胆固醇、低密度脂蛋白胆固醇和致动脉粥样硬化指数升高，而高密度脂蛋白胆固醇水平没有变化。这些数据表明，CMS 诱导的生理和形态变化可能通过与 NO 生成不足和血脂异常相关的机制促进动脉粥样硬化的发展。
