Green Tea Extract (CUMC6335), not Epigallocatechin Gallate, Cause Vascular Relaxation in Rabbits

  • Lim, Dong-Yoon (Department of Pharmacology, College of Medicine, Chosun University) ;
  • Baek, Young-Joo (Department of Pharmacology, College of Medicine, Chosun University) ;
  • Lee, Eun-Bang (Natural Products Research Institute, Seoul National University)
  • Published : 2004.10.30

Abstract

The aim of the present study was to examine whether green tea extract (CUMC6335) affects the blood pressure and the isolated aortic contractility of the rabbit in comparison with one of the most powerful active catechins, epigallocatechin gallate (EGCG). The phenylephrine $(1-10\;{\mu}M)-induced$ contractile responses were greatly inhibited in the presence of CUMC6335 (0.3-1.2 mg/ml). Also, high potassium (56 mM)-induced contractile responses were depressed in high concentration (0.6-1.2 mg/ml), but not affected in low concentration CUMC6335 (0.3 mg/ml). However, epigallocatechin gallate $(EGCG,\;4-12\;{\mu}g/ml)$ did not affect the contractile responses evoked by phenylephrine and high $K^+$. The infusion of CUMC6335 with a rate of 20 mg/kg/30 min made a significant reduction in pressor responses induced by intravenous norepinephrine. However, EGCG (1 mg/kg/30 min) did not affect them. Collectively, these results obtained from the present study suggest that intravenous CUMC6335 causes depressor action in the anesthetized rat at least partly through the blockade of adrenergic ${\alpha}_1-receptors$. CUMC6335 also causes the relaxation in the isolated aortic strips of the rabbit partly via the blockade of adrenergic ${\alpha}_1-receptors$, in addition to the unknown direct mechanism. It seems that there is no species difference in the vascular effect between the rat and the rabbit.

Keywords

References

  1. Abe Y, Umemura S, Sugimoto K, Hirawa N, Kato Y, Yokoyama N, Yokoyama T, Iwai J, and Ishii M, Effect of green tea rich in gamma-aminobutynic acid on blood pressure of Dahl salt-sensitive rats. Am J Hypertens 8, 74-79 (1995) https://doi.org/10.1016/0895-7061(94)00141-W
  2. Ablad B, Borg KO, Carlsson E, Johnson G, Malmfors L, and Regardh CG. A survey of the pharmacological properdes of metoprolol in animals and man. Acta Pharmacot Toxicol (Copenh) 36(5), 7-23 (1975)
  3. Balentine DA, Wiseman SA, and Bouwens LCM, The chemistry of tea flavo-noids. Crit Rev Food Sci Nut 37, 693-704 (1997) https://doi.org/10.1080/10408399709527797
  4. Bevan JA, Selective action of diltiazem on cerebral vascular smooth muscle in the rabbit: antagonism of extrinsic but not intrinsic maintained tone. Am J Cardiol 46, 519-524 (1982)
  5. Bingham SA, Vorster H, Jerling JC, Magee E, Mulligan A, Runswick SA, and Cummings JH. Effect of tea drinking on blood lipids, blood pressure and aspects of bowel habit. Br J Nutr 78, 41-45 (1997) https://doi.org/10.1079/BJN19970117
  6. Bolton TM, Mechanisms of action of transmitters and other substances on smooth muscle. Physiot Rev 3, 606-718 (1979)
  7. Conney AH, Wang ZY, Huang MT, Ho CT, and Yang CS. Inhibitory efFect of green tea on tumoiigenesis by chemicals and ultraviolet light. Prev Med 21, 361-369 (1992) https://doi.org/10.1016/0091-7435(92)90043-H
  8. Constandne JW, Mcshane WK, Scnabine A, and Hess HJ. Analysis of the hypotensive action of prazosin. In: Hypertension, Mechanisms and Management ed. by Onesti G, Kim KE, Moyer JH, Grume & Stratton Inc, New York, p 429, 1973
  9. De Whalley CV, Rankin SM, Hoult JRS, Jessup W, and Leake DS, Flavonoids inhibit the oxidative modification of low density lipoproteins by macrophages. Biochem Pharmacol 39, 1743-1750 (1990) https://doi.org/10.1016/0006-2952(90)90120-A
  10. Dube GP, Baik YH, and Schwartz A, Effects of novel calcium channel agonist dihydropyridine analogue, Bay K 8644, on pig co ronary artery: Biphasic mechanical response and pa radoxical potentiation of contraction by diltiazem and ni modipine. J Cardiovasc Phannacol 7, 377-389 (1985) https://doi.org/10.1097/00005344-198503000-00025
  11. Dube GP, Baik YH, Van Breemen C, and Schwartz A, Effects of isosorbide dinitrate and diltiazem on $Ca^{2+}$ flux and contraction in artery. European J Pharmacol 145, 39-47 (1988) https://doi.org/10.1016/0014-2999(88)90346-9
  12. Fitzpatrick DF, Hirschfield SL, and Coffey RG, Endothelium-dependent vasorelaxing activity of wine and other grape products. Am J Physiol 265, H77-78 (1993)
  13. Fitzpatrick DP, Hirschfield SL, Ricci T, Jantzen P, and Coffey RG, Endothelium-dependent vasorelaxation caused by various plant extracts. J Cardiovasc Pharmacol 26, 90-95 (1995) https://doi.org/10.1097/00005344-199507000-00015
  14. Fleckenstein A, Specific pharmacology of calcium in myocardium,cardiac pacemakers, and vascular smooth muscle. Ann Rev Pharmacol Toxicol 17, 149-166 (1977) https://doi.org/10.1146/annurev.pa.17.040177.001053
  15. Freis EE, Mackey JD, and Oliver WF, The effect of sympatholytic drugs on the cardiovascular responses to epinephrine and norepinephrine in man. Cir Res 3, 254 (1951)
  16. Fujiki H, Yoshizawa S, Hohuchi T, Suganuma M, Yatsunami J, and Nishiwaki S, Anticardnogenic effects of (-)-epigallocatechin gallate. Prev Med 21, 503-509 (1992) https://doi.org/10.1016/0091-7435(92)90057-O
  17. Graham HN, Green tea consumption and polyphenol chemistry. Prev Med 21, 334-350 (1992) https://doi.org/10.1016/0091-7435(92)90041-F
  18. Henry JP, and Stephens-Larson P, Reduction of chronic psychosocial hypertension in mice by decaffeinated tea. Hypertension 6(3), 437-444, 1984 https://doi.org/10.1161/01.HYP.6.3.437
  19. Hertog, MGL, Feskens EJM, Hollman PCH, Katan MB, and Kromhout D. Dietary aiitioxidant flavonoids and risk of co ronary heart disease: the Zutphen Elderly Study. Lancet 342, 1007-1011 (1993) https://doi.org/10.1016/0140-6736(93)92876-U
  20. Hodgson JM, Puddey IB, Byrke V, Beilin LJ, and Jordan, N, Effects on blood pressure of drinking green and black tea. J Hypert 17, 457-463 (1999) https://doi.org/10.1097/00004872-199917040-00002
  21. Huang Y, Zhang AQ, Lau CW, and Chen ZY, Vasorelaxant effect of purified green tea epicatechin derivatives in rat mesenteric artery. Life Sci 63, 275-283 (1998) https://doi.org/10.1016/S0024-3205(98)00273-2
  22. Huang Y, Chan NWK, Lau CW, Yao XQ, Chan FL, and Chen ZY, Involvement of endothelium/nitric oxide in vasorelaxation in duced by purified green tea (-) epicatechin. Biohim Biophys Acta 1427, 322-328 (1999) https://doi.org/10.1016/S0304-4165(99)00034-3
  23. Imai S, Kitagawa. A comparison of the differential effects of nitroglycenn, nifedipine, and papaverine on contractures in duced in vascular and intestinal smooth muscle by potassium and lanthanum. Jap J Pharmacol 31, 193 (1981) https://doi.org/10.1254/jjp.31.193
  24. Ito Y, Kitamura K, and Kuriyama H, Actions of nitroglycenn on the membrane and mechanical properties of smooth muscles of the coronary artery of the pig. Br J Pharmacol 70, 197-204 (1980) https://doi.org/10.1111/j.1476-5381.1980.tb07925.x
  25. Ito Y, Kitamura K, and Kuriyama H, Nitroglycerin and catecholamine actions on smooth muscle cells of carmine coronary artery. J Physiol(London) 309, 171-183 (1980) https://doi.org/10.1113/jphysiol.1980.sp013502
  26. Keli SO, Hertog MGL, Feskens EIM, and Kromhout D, Dietary Havonoids, antioxidant vitamins, and incidence of stroke. Arch Intern Med 156, 637-642 (1996) https://doi.org/10.1001/archinte.156.6.637
  27. Kim JM, Park KO, and Baik YH, Effects of antiepileptic drugs on contractile responses of vascular smooth muscles. Chonnam. J Med Sci 2(1), 50-59 (1989)
  28. Lim DY, Lee ES, Park HG, Kim BC, Hong SP, and Lee EB, Comparison of Green Tea Extract and Epigallocatechin gallate on Blood Pressure and Contractile Responses of Vascular Smooth Muscle of Rats. Arch Pharm Res 26(3), 214-223 (2003) https://doi.org/10.1007/BF02976833
  29. Lim DY, Park HG, and Lee BR, Green Tea Extract, not Epigallocatechin gallate Inhibits Catecholamine Release From the Rat Adrenal Medulla. J Apptied Pharmacol 11(1), 33-40 (2003)
  30. Pincomb GA, Lovallo WR, Mckey BS, Sung, BH, Passey RB, and Everson SA, Acute blood pressure elevations with caffeine in men with borderline systemic hypertension. Am J Cardiol 77, 270-274 (1996) https://doi.org/10.1016/S0002-9149(97)89392-7
  31. Quinlan P, Lane J, and Aspinal L, Effects of hot tea, coffee and water ingestion on physiological responess and mood: role of ca ffeine, water and beverage type. Psychopharmacology 134, 164-173 (1997) https://doi.org/10.1007/s002130050438
  32. Rakic V, Beilin LJ, and Burke V, Effect of coffee and tea drinking on postprandial hypotension in older men and women. Ciln Exp Pharmacol Physiol 23, 559-563 (1996) https://doi.org/10.1111/j.1440-1681.1996.tb02779.x
  33. Ricc-Evans CA, Miller NJ, Bolwell PG, Bramley PM, and Pridham JB, The relative antioxidant activities of plant-denved po lyphenolic Havonoids. Free Rad Res 22, 375-383 (1995) https://doi.org/10.3109/10715769509145649
  34. Sano M, Takenaka Y, Kojima R, Saito SI, Tomita I, and Katou M, Effects of pu-erh tea on lipid metabolism in rats. Chem Pharm Bull 34, 221-228 (1986) https://doi.org/10.1248/cpb.34.221
  35. Schwartz A and Taira N, Calcium channel-blocking drugs: A novel intervention for the treatment of cardiac disease. Circ Res (American Heart association Monograph) 52, 1-183 (1983) https://doi.org/10.1161/01.RES.52.1.1
  36. Schwartz A and Triggle DJ. Cellular action of calcium blocking drugs. Ann Rev Med 35, 325-339 (1984) https://doi.org/10.1146/annurev.me.35.020184.001545
  37. Stensvold I, Tverdal A, Solvoll K, and Foss OP, Tea consumption. Relationship to cholesterol, blood pressure, and coronary and total mortality. Prev Med 21, 546-553 (1992) https://doi.org/10.1016/0091-7435(92)90062-M
  38. Sung BH, Whitsett TL, Lovallo WR, Absi M, Pincomv GA, and Wilson MF, Prolonged increase in blood pressure by a single orial dose of caffeine in mildly hypertensive men. Am J Hypertens 7, 755-756 (1994) https://doi.org/10.1093/ajh/7.8.755
  39. Tallarida RJ and Murray RB, Manual of pharmamtogic calcutations with computer programs. 2nd ed. Spnnger-Verlag, New York, p 132, (1987)
  40. Watkins RW and Davidson IWF, Comparative efFects of nitroprusside and nitrogiycerin: Actions on phasic and tonic components of arterial smooth muscle contraction. European J Pharmacol 62, 191-200 (1980) https://doi.org/10.1016/0014-2999(80)90275-7
  41. Wang ZY, Cheng SJ, Zhou ZC, Athar M, Khan WA, and Bickers DR, Antimutagenic activity of green tea polyphenols. Mutat Res 223, 273-285 (1989) https://doi.org/10.1016/0165-1218(89)90120-1
  42. Yokozawa T, Oura H, Sakanaka S, Ishigaki S, and Kim M, Depressor effect of tannin in green tea on rats with renal hypertension. Biosci Biotech Biochem 58, 855-858 (1994) https://doi.org/10.1271/bbb.58.855
  43. Yokogoshi H, Kato Y, Saesaka YM, Takihara-Matsura T, and Takeuchi N, Reduction effect of theanine on blood pressure and brain 5-hydroxyindoles in spontaneously hypertensive rats. Biosci Biotech Biochem 59, 615-618 (1995) https://doi.org/10.1271/bbb.59.615
  44. Yoshizawa S, Horiuchi T, Fujiki H, Yoshida T, Okuda T, and Sugimura T, Antitumor promoting acdvity of (-)-epigallocatechin gallate, the main constituent of 'tannin' in green tea. Phytotherapy Res 1, 44-47 (1987) https://doi.org/10.1002/ptr.2650010110
  45. Young W, Hotovec RL, and Romero AG, Tea and atherosclerosis. Nature 216, 1015-1016 (1967) https://doi.org/10.1038/2161015a0