Rousseau-Ralliard Delphine, Moreau Daniel, Guilland Jean-Claude, Raederstorff Daniel, Grynberg Alain
INRA (Institut National de la recherche Agronomique), UMR-A 1154, Laboratoire Lipides Membranaires et Régulation Fonctionnelle du Coeur et des Vaisseaux, Faculté de Pharmacie, Châtenay-Malabry 92290, France.
Prostaglandins Leukot Essent Fatty Acids. 2009 May-Jun;80(5-6):269-77. doi: 10.1016/j.plefa.2009.03.003. Epub 2009 May 9.
This study was designed to evaluate the effects of individual dietary long-chain n-3 polyunsaturated fatty acids (LCPUFA) on hypertension and cardiac consecutive disorders in spontaneously hypertensive rats (SHR) as compared to Wistar-Kyoto rats (WKY). Rats were fed for 2 months an eicosapentaenoic (EPA)- or docosahexaenoic acid (DHA)-rich diet (240 mg/day) or an n-3 PUFA-free diet. Male SHR (n=6), implanted with cardiovascular telemetry devices, were housed in individual cages for continuous measurements of cardiovascular parameters (blood pressure (BP) and heart rate (HR)) during either activity or rest periods, ECG were recorded during the quiet period. The n-6 PUFA upstream of arachidonic acid was affected in SHR tissues. The cardiac phospholipid fatty acid profile was significantly affected by dietary DHA supply, and EPA in a very lower extent, since DHA only was incorporated in the membranes instead of n-6 PUFAs. Endothelium n-6 PUFA content increased in all SHR groups. Compared to WKY, linoleic acid content decreased in both studied tissues. Cardiac noradrenalin decreased while the adrenal catecholamine stores decreased in SHR as compared to WKY. Both n-3 PUFA supply induced a decrease of adrenal catecholamine stores. Nevertheless after 6 weeks, DHA but not EPA induced a lowering-blood pressure effect and shortened the QT interval in SHR, most probably through its tissue enrichment and a specific effect on adrenergic function. Dietary DHA supply retards blood pressure development and has cardioprotective effect. These findings, showing the cardioprotective effects of DHA in living animals, were obtained in SHR, but may relate to essential hypertension in humans.
本研究旨在评估与Wistar-Kyoto大鼠（WKY）相比，个体饮食中的长链n-3多不饱和脂肪酸（LCPUFA）对自发性高血压大鼠（SHR）高血压及心脏相关疾病的影响。将大鼠分为三组，分别喂食富含二十碳五烯酸（EPA）或二十二碳六烯酸（DHA）的饮食（240毫克/天）或不含n-3多不饱和脂肪酸的饮食，持续2个月。对植入心血管遥测装置的雄性SHR（n = 6）单独饲养在笼中，以便在活动期或休息期连续测量心血管参数（血压（BP）和心率（HR）），并在安静期记录心电图。SHR组织中花生四烯酸上游的n-6多不饱和脂肪酸受到影响。膳食DHA供应显著影响心脏磷脂脂肪酸谱，而EPA的影响程度非常低，因为只有DHA被纳入细胞膜而不是n-6多不饱和脂肪酸。所有SHR组的内皮n-6多不饱和脂肪酸含量均增加。与WKY相比，两个研究组织中的亚油酸含量均降低。与WKY相比，SHR的心脏去甲肾上腺素减少，肾上腺儿茶酚胺储备减少。两种n-3多不饱和脂肪酸供应均导致肾上腺儿茶酚胺储备减少。然而，6周后，DHA而非EPA在SHR中产生了降压作用并缩短了QT间期，这很可能是通过其在组织中的富集以及对肾上腺素能功能的特定作用实现的。膳食DHA供应可延缓血压升高并具有心脏保护作用。这些在SHR中获得的结果表明DHA在活体动物中具有心脏保护作用，可能与人类原发性高血压有关。
