Coatmellec-Taglioni Gwenn, Dausse Jean-Pierre, Giudicelli Yves, Ribière Catherine
Department of Biochemistry and Molecular Biology, Faculté de Médecine de Paris-Ouest, Université René Descartes, France.
Am J Hypertens. 2002 Feb;15(2 Pt 1):143-9. doi: 10.1016/s0895-7061(01)02269-5.
Although the pathogenesis of the obesity-related hypertension is not fully understood, prevalence of the cardiovascular complications is much higher in obese men than obese women. In a recent study, we reported that male rats fed a cafeteria diet, while becoming obese, developed hypertension and important changes in their renal alpha2-adrenergic receptor subtypes distributions. The aim of the present study was to investigate whether these alterations are sex dependent. After 10 weeks of the cafeteria diet, male and female rats had the same increase in fat pad weight and in plasma leptin levels. However, in contrast to males, females had normal blood pressure (BP). On the basis of radioligand-binding studies using [3H]-RX821002 and confirming our recent observation, an increase in alpha2-adrenergic receptor densities occurred in kidneys of cafeteria-fed male but not female rats. Moreover, in contrast with the situation observed in males, ligand competition studies failed to reveal any change in the renal alpha2A- and alpha2B-adrenergic receptors subtypes distribution in females. Finally, in the cafeteria-fed females reverse transcription-polymerase chain reaction experiments showed unaltered expression of these two alpha2-adrenergic receptor subtypes. These data thus suggest a strong relationship between the sexual dimorphism in the cafeteria diet-induced hypertension and altered expression of the alpha2-adrenergic receptor subtypes in the kidney.
尽管肥胖相关高血压的发病机制尚未完全明确，但肥胖男性心血管并发症的患病率远高于肥胖女性。在最近的一项研究中，我们报告称，喂食自助餐饮食的雄性大鼠在变得肥胖的同时，出现了高血压以及肾脏α2 - 肾上腺素能受体亚型分布的重要变化。本研究的目的是调查这些改变是否存在性别依赖性。在自助餐饮食10周后，雄性和雌性大鼠的脂肪垫重量和血浆瘦素水平均有相同程度的增加。然而，与雄性大鼠不同的是，雌性大鼠的血压正常。基于使用[3H]-RX821002的放射性配体结合研究，并证实了我们最近的观察结果，喂食自助餐的雄性大鼠而非雌性大鼠的肾脏中α2 - 肾上腺素能受体密度增加。此外，与雄性大鼠的情况相反，配体竞争研究未能揭示雌性大鼠肾脏中α2A - 和α2B - 肾上腺素能受体亚型分布有任何变化。最后，在喂食自助餐的雌性大鼠中，逆转录 - 聚合酶链反应实验表明这两种α2 - 肾上腺素能受体亚型的表达未发生改变。因此，这些数据表明自助餐饮食诱导的高血压中的性别差异与肾脏中α2 - 肾上腺素能受体亚型表达的改变之间存在密切关系。
