摘要
目的:观察有氧运动对自发性高血压大鼠(SHR)离体胸主动脉反应性及电压门控钾通道(KV)蛋白表达的影响,探讨运动降低血压的血管平滑肌钾通道机制。方法:24只雄性SHR随机平均分为安静组(SHR-SED)和运动组(SHR-EX),另选用同龄雄性WKY大鼠作为正常血压对照组。SHR-EX组进行8周有氧运动,坡度0°,20 m/min,60 min/d,5 d/周。8周后,检验离体胸主动脉对去甲肾上腺素(NE)、4-氨基吡啶(4-AP)的反应性。另用免疫组化DAB法和Western blot法测定胸主动脉平滑肌KV1.2和KV1.5的表达情况。结果:1)SHR-EX组血压显著低于SHR-SED组1)SHR-EX组离体胸主动脉对NE的敏感性小于SHR-SED组。2)4-AP诱发的血管收缩反应在SHE-EX组中显著大于SHR-SED组。3)SHR-EX组KV1.2和KV1.5表达均显著高于SHE-SED组,有氧运动显著抑制KV1.2和KV1.5表达的下调。结论:长期规律的有氧运动训练可降低SHR的收缩压,减弱胸主动脉对缩血管物质的反应性,其重要机制之一为有氧运动显著抑制高血压诱导的平滑肌细胞KV通道蛋白表达下调。
Objectives： This paper aims to investigate the effect of aerobic exercise on the vascular reactivity of thoracic aorta and voltage-gated potassium channel （Kv ） expression in spontaneously hypertensive rats （SHR） ,and to explore the possible potassium channel mechanisms in vascular smooth muscle cells （VSMCs） underlying the beneficial effects of exercise training on hypertension. Methods ： Twenty-four male SHRs were randomly assigned to a sedentary group （SHR-SED） and an exercise training group （SHR-EX）. SHR-EX underwent treadmill training at 20 m/min for 60 min/d ,5 d/wk ,for 8 weeks. Age-matched male WKY rats were used as control. Vascular contractility of thoracic aortas in response to norepinephrine （NE） and 4 -aminopyridine （4 -AP, a selective Kv channel blocker） was measured. Immunohistochemistry and western blotting were performed to examine the expressions of Kv 1.2 and Kv 1.5. Results ： The NE sensitivity of aorta rings was SHR-SED 〉 SHR-EX 〉 WKY. 4 - AP induced a significant increase of vessel tension in all three groups. The maximal tension increased by 4 - AP was SHR-SED 〈 SHR-EX 〈 WKY. Immunohistochemistry and western blotting showed that Kv 1.2 and Kv 1.5 expressions were significantly decreased in hypertension and exercise training attenuated this reduction. Conclusion： Regular aerobic exercise training attenuates SHR-related down-regulation of Kvl. 2 and Kv1. 5 expression in VSMCs,which may be an important mechanism underlying the beneficial effects of exercise training on hypertension and arterial function.
出处
《北京体育大学学报》
CSSCI
北大核心
2014年第6期49-53,共5页
Journal of Beijing Sport University
基金
国家自然科学基金(31371201)
新世纪优秀人才培养资助(NCET-11-0850)
关键词
有氧运动
自发性高血压大鼠
胸主动脉平滑肌
KV通道
aerobic exercise
spontaneously hypertensive rat
thoracic aorta smooth muscle cell
Kv channel
