title: Inhibitory effects of purified green tea epicatechins on contraction and proliferation of arterial smooth muscle cells.
abstract: OBJECTIVE
  The present study was aimed to examine the vasorelaxant and antiproliferative responses to purified green tea epicatechin mixture, (-)epicatechin and (-)epigallocatechin gallate on rat arterial smooth muscle cells.
  
  
  METHODS
  Changes in isometric force were measured by Grass force transducer and effects on cell proliferation were evaluated using [3H]thymidine incorporation assay.
  
  
  RESULTS
  Epicatechin mixture, (-)epicatechin and (-)epigallocatechin gallate, which we isolated and purified from jasmine green tea, concentration-dependently, reduced the contractile response to phenylephrine in rat isolated aortic rings with (-)epigallocatechin gallate being more effective. These three agents also inhibited [3H]thymidine incorporation into DNA in cultured rat aortic smooth muscle cells in a concentration-dependent manner.
  
  
  CONCLUSIONS
  The purified epicatechin derivatives from jasmine green tea relaxed the isolated rat arteries preconstricted by phenylephrine and inhibited aortic smooth muscle cell proliferation.
authors.affiliation: Departments of Biochemistry and Department of Physiology, Faculty of Medicine, Chinese University of Hong Kong, Shatin, Hong Kong, China.
authors.forename: Z Y
authors.initials: ZY
authors.lastname: Chen
authors.forename: W I
authors.initials: WI
authors.lastname: Law
authors.forename: X Q
authors.initials: XQ
authors.lastname: Yao
authors.forename: C W
authors.initials: CW
authors.lastname: Lau
authors.forename: W K
authors.initials: WK
authors.lastname: Ho
authors.forename: Y
authors.initials: Y
authors.lastname: Huang
mesh_terms: D000818:Animals; D001013:Aorta, Thoracic / Q000166:cytology; D002392:Catechin / Q000031:analogs & derivatives* / Q000302:isolation & purification / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects; D066298:In Vitro Techniques; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D009131:Muscle, Smooth, Vascular / Q000166:cytology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013662:Tea / Q000737:chemistry; D014665:Vasodilator Agents / Q000494:pharmacology
chemical_list: D013662:Tea; D014665:Vasodilator Agents; D002392:Catechin; C062669:epicatechin gallate; C045651:epigallocatechin gallate