Department of Physiological Sciences, State University of Londrina, Londrina, Paraná, Brazil.
Life Sci. 2010 Sep 11;87(11-12):375-81. doi: 10.1016/j.lfs.2010.07.014. Epub 2010 Aug 3.
the purpose of the present work was to investigate the effect of cyclooxygenase-2 (COX-2) inhibition on the cardiovascular and inflammatory aspects promoted by monosodium glutamate (MSG)-induced obesity in rats.
Neonatal Wistar male rats were injected with MSG (4 mg/g body weight ID) or equimolar saline (control). Treatment with celecoxib (50 mg/kg ip) or saline (0.9% NaCl ip) began at 60 days of age. At 90 days, all rats were anesthetized for catheterization of the femoral artery, and the mean arterial pressure (MAP) and heart rate (HR) were recorded once consciousness was regained.
MSG obese rats were hypertensive (MAP=138±4 mm Hg) compared with controls (MAP=118±2 mm Hg). After treatment with celecoxib, the hypertension was attenuated (MAP=126±2 mm Hg) in obese rats without changes in HR. The retroperitoneal and periepididymal fat weighed more in obese rats (Obese: Retro=7.08±0.51, Peri=6.36±0.81, CONTROL: Retro=3.60±0.46; Peri=3.24±0.42), but celecoxib did not alter these parameters. Plasma nitric oxide levels were not different between groups. However, the level of plasma prostaglandins, the immunohistochemical staining of COX-2 in cardiac tissue and plasma lipoperoxidation were higher in obese rats, and celecoxib attenuated these parameters. MSG produced liver steatosis that was also attenuated following celecoxib treatment.
Our data demonstrate an association between increased blood pressure and products of COX-2 in obese rats, suggesting a role for prostaglandins in the hypertensive and inflammatory aspects of MSG-induced obesity.
本研究旨在探讨环氧化酶-2（COX-2）抑制对谷氨酸单钠（MSG）诱导肥胖大鼠心血管和炎症方面的影响。
新生 Wistar 雄性大鼠经腹腔注射 MSG（4mg/g 体重）或等摩尔生理盐水（对照组）。60 天时开始给予塞来昔布（50mg/kg，腹腔注射）或生理盐水（0.9%NaCl，腹腔注射）治疗。90 天时，所有大鼠麻醉后行股动脉置管术，意识恢复后记录平均动脉压（MAP）和心率（HR）。
与对照组（MAP=118±2mmHg）相比，MSG 肥胖大鼠血压升高（MAP=138±4mmHg）。用塞来昔布治疗后，肥胖大鼠的高血压减轻（MAP=126±2mmHg），但 HR 无变化。肥胖大鼠的腹膜后和附睾脂肪重量增加（肥胖组：Retro=7.08±0.51，Peri=6.36±0.81，对照组：Retro=3.60±0.46，Peri=3.24±0.42），但塞来昔布对这些参数没有影响。各组间血浆一氧化氮水平无差异。然而，肥胖大鼠的血浆前列腺素水平、心肌组织 COX-2 的免疫组织化学染色和血浆脂质过氧化水平升高，塞来昔布可减轻这些参数。MSG 导致的肝脂肪变性也在塞来昔布治疗后减轻。
我们的数据表明，肥胖大鼠血压升高与 COX-2 产物之间存在关联，提示前列腺素在 MSG 诱导肥胖的高血压和炎症方面发挥作用。
