BACKGROUND: 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 - C. sinensis, C. ptilophylla and C. assamica var. kucha - on blood pressure (BP) and heart rate in spontaneously hypertensive rats (SHRs). RESULTS: Intragastric administration of C. sinensis extract led to an acute increase in systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate in SHRs. However, C. ptilophylla and C. assamica var. kucha exerted no obvious influences on SBP, DBP or heart rate. Similar to the extract of C. sinensis, 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 C. ptilophylla and C. assamica var. kucha, respectively - had no pressor effects. The effect of caffeine on BP was related to the regulation of plasma epinephrine and norepinephrine levels in SHRs. CONCLUSION: The different effects of C. sinensis, C. ptilophylla and C. assamica var. kucha on BP might be explained, at least partially, by the differences in the varieties and contents of purine alkaloids.
BACKGROUND: Heavy tea consumption is suggested to be unsuitable for hypertensivepeople. However, the bioactive substances in different varieties of tea leaves are very different. This study compares the effects of three Chinese teas - C. sinensis, C. ptilophylla and C. assamica var. kucha - on blood pressure (BP) and heart rate in spontaneously hypertensiverats (SHRs). RESULTS: Intragastric administration of C. sinensis extract led to an acute increase in systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate in SHRs. However, C. ptilophylla and C. assamica var. kucha exerted no obvious influences on SBP, DBP or heart rate. Similar to the extract of C. sinensis, 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 C. ptilophylla and C. assamica var. kucha, respectively - had no pressor effects. The effect of caffeine on BP was related to the regulation of plasma epinephrine and norepinephrine levels in SHRs. CONCLUSION: The different effects of C. sinensis, C. ptilophylla and C. assamica var. kucha on BP might be explained, at least partially, by the differences in the varieties and contents of purine alkaloids.
Authors: Hui He; Dejian Ma; Laura Brooks Crone; Matthew Butawan; Bernd Meibohm; Richard J Bloomer; Charles R Yates Journal: J Caffeine Res Date: 2017-09-01
Authors: Amy Clewell; Gábor Hirka; Róbert Glávits; Philip A Palmer; John R Endres; Timothy S Murbach; Tennille Marx; Ilona Pasics Szakonyiné Journal: J Toxicol Date: 2016-08-22
Authors: Timothy S Murbach; Róbert Glávits; John R Endres; Amy E Clewell; Gábor Hirka; Adél Vértesi; Erzsébet Béres; Ilona Pasics Szakonyiné Journal: J Toxicol Date: 2019-10-27
Authors: Trisha A VanDusseldorp; Matthew T Stratton; Alyssa R Bailly; Alyssa J Holmes; Michaela G Alesi; Yuri Feito; Gerald T Mangine; Garrett M Hester; Tiffany A Esmat; Megan Barcala; Karleena R Tuggle; Michael Snyder; Andrew S Modjeski Journal: Nutrients Date: 2020-02-28 Impact factor: 5.717