绿茶的抗氧化作用可降低高血压实验模型中的血压并减轻交感神经兴奋。

The antioxidant effects of green tea reduces blood pressure and sympathoexcitation in an experimental model of hypertension.

作者信息

Garcia Michelle L, Pontes Roberto B, Nishi Erika E, Ibuki Flávia K, Oliveira Vanessa, Sawaya Alexandra C H, Carvalho Patrícia O, Nogueira Fernando N, Franco Maria do Carmo, Campos Ruy R, Oyama Lila M, Bergamaschi Cássia T

机构信息

aDepartment of Physiology, Escola Paulista de Medicina, Universidade Federal de São PaulobDepartment of Biomaterials and Oral Biology, Faculdade de Odontologia, Universidade de São PaulocDepartment of Medicine, Universidade Federal de São Paulo, São PaulodDepartment of Plant Biology, Universidade Estadual de Campinas, CampinaeLaboratory of Multidisciplinary Research, Universidade São Francisco, São Paulo, Brazil.

出版信息

J Hypertens. 2017 Feb;35(2):348-354. doi: 10.1097/HJH.0000000000001149.

DOI:10.1097/HJH.0000000000001149

PMID:28005704

Abstract

BACKGROUND

Oxidative stress is a key mediator in the maintenance of sympathoexcitation and hypertension in human and experimental models. Green tea is widely known to be potent antioxidant.

OBJECTIVE

We aimed to evaluate the effects of green tea in a model of hypertension.

METHODS

Hypertension was induced by the nitric oxide synthase inhibitor [N-nitro-L-arginine-methyl-ester (L-NAME); 20 mg/kg per day, orally, for 2 weeks] in male Wistar rats. After the first week of L-NAME treatment, animals received green tea ad libitum for 1 week. At the end of the treatment period, blood pressure, heart rate, baroreflex sensitivity, renal sympathetic nerve activity, and vascular and systemic oxidative stress were assessed.

RESULTS

L-NAME-treated animals exhibited an increase in blood pressure (165 ± 2 mmHg) compared with control rats (103 ± 1 mmHg) and green tea treatment reduced hypertension (119 ± 1 mmHg). Hypertensive animals showed a higher renal sympathetic nerve activity (161 ± 12 spikes/s) than the control group (97 ± 2 spikes/s), and green tea also decreased this parameter in the hypertensive treated group (125 ± 5 spikes/s). Arterial baroreceptor function and vascular and systemic oxidative stress were improved in hypertensive rats after green tea treatment.

CONCLUSIONS

Taken together, short-term green tea treatment improved cardiovascular function in a hypertension model characterized by sympathoexcitation, which may be because of its antioxidant properties.

摘要

背景

氧化应激是人类和实验模型中维持交感神经兴奋和高血压的关键介质。众所周知，绿茶是一种强效抗氧化剂。

目的

我们旨在评估绿茶在高血压模型中的作用。

方法

通过一氧化氮合酶抑制剂[N-硝基-L-精氨酸甲酯（L-NAME）；每天20毫克/千克，口服，持续2周]诱导雄性Wistar大鼠患高血压。在L-NAME治疗的第一周后，动物自由饮用绿茶1周。在治疗期结束时，评估血压、心率、压力反射敏感性、肾交感神经活动以及血管和全身氧化应激。

结果

与对照大鼠（103±1毫米汞柱）相比，接受L-NAME治疗的动物血压升高（165±2毫米汞柱），而绿茶治疗可降低高血压（119±1毫米汞柱）。高血压动物的肾交感神经活动（161±12次/秒）高于对照组（97±2次/秒），绿茶也降低了高血压治疗组的这一参数（125±5次/秒）。绿茶治疗后，高血压大鼠的动脉压力感受器功能以及血管和全身氧化应激得到改善。