Differing chemical compositions of three teas may explain their different effects on acute blood pressure in spontaneously hypertensive rats. (24th July 2014)

• Record Type: Journal Article
• Authors: Li, Shan‐Bing; Li, Yi‐Fang; Mao, Zhong‐Fu; Hu, Hui‐Hua; Ouyang, Shu‐Hua; Wu, Yan‐Ping; Tsoi, Bun; Gong, Pin; Kurihara, Hiroshi; He, Rong‐Rong
• Is Part Of: Journal of the science of food and agriculture. Volume 95:Number 6(2015:Apr. 15)
• Page Start: 1236
• Page End: 1242
• Publication Date: 2014-07-24
• Subjects: Food -- Periodicals; Agriculture -- Periodicals; 664
• DOI: 10.1002/jsfa.6811
• Languages: English
• ISSNs: 0022-5142

Abstract

<abstract abstract-type="main" id="jsfa6811-abs-0001"> <title>Abstract</title> <sec id="jsfa6811-sec-0001" sec-type="section"> <title>BACKGROUND</title> <p id="jsfa6811-para-0001">Heavy tea consumption is suggested to be unsuitable for hypertensive people. However, the bioactive substances in different varieties of tea leaves are very different. This study compares the effects of three Chinese teas – <italic>C. sinensis</italic>, <italic>C. ptilophylla</italic> and <italic>C. assamica</italic> var. <italic>kucha</italic> – on blood pressure (BP) and heart rate in spontaneously hypertensive rats (SHRs).</p> </sec> <sec id="jsfa6811-sec-0002" sec-type="section"> <title>RESULTS</title> <p id="jsfa6811-para-0002">Intragastric administration of <italic>C. sinensis</italic> extract led to an acute increase in systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate in SHRs. However, <italic>C. ptilophylla</italic> and <italic>C. assamica</italic> var. <italic>kucha</italic> exerted no obvious influences on SBP, DBP or heart rate. Similar to the extract of <italic>C. sinensis</italic>, intragastric administration of caffeine also led to an acute increase in BP and heart rate in SHRs. In contrast, theobromine and theacrine – purine alkaloids predominantly contained in <italic>C. ptilophylla</italic> and <italic>C. assamica</italic> var. <italic>kucha</italic>, respectively – had no pressor effects. The effect of caffeine on BP was related to the regulation of plasma epinephrine and norepinephrine levels in SHRs.</p> </sec> <sec id="jsfa6811-sec-0003" sec-type="section"> <title>CONCLUSION</title> <p id="jsfa6811-para-0003">The different effects of <italic>C. sinensis</italic>, <italic>C. ptilophylla</italic> and <italic>C. assamica</italic> var. <italic>kucha</italic> on BP might be explained, at least partially, by the differences in the varieties and contents of purine alkaloids. © 2014 Society of Chemical Industry</p> </sec> </abstract>