title: Preventive effects of green tea catechins on spontaneous stroke in rats.
abstract: BACKGROUND
  Green tea catechins possess potent antioxidative properties and protect against various oxidative diseases. Malignant stroke-prone spontaneously hypertensive rats (M-SHRSP) develop severe hypertension and spontaneous stroke at early ages. We previously reported that ingestion of green tea catechins prevents cerebral ischemic damage in a middle cerebral artery occlusion and reperfusion rat stroke model, in association with increased plasma epigallocatechin-gallate (EGCG) concentrations. In this study, we examined whether tea catechin intake decreases the incidence of spontaneous stroke in M-SHRSP.
  
  
  METHODS
  Male M-SHRSP ingested 0.5% green tea catechin extract (Polyphenon E) in their drinking water beginning at 5 weeks of age, and blood pressure, heart rate, and locomotor activity were continuously monitored from 8 weeks using a telemetry system. Stroke onset was assessed by the appearance of neurologic symptoms, body weight loss, and circadian rhythm disturbances in heart rate, blood pressure, and locomotor activity.
  
  
  RESULTS
  Tea catechin ingestion significantly delayed stroke onset by 10 days compared to the control group. Although there was no difference in blood pressure at 10 weeks, the rate of in blood pressure increase in the tea catechin group was significantly smaller than that in the control group. Plasma NO2- and NO3- concentrations increased after stroke in both groups without significant difference between the two groups. Plasma EGCG concentration significantly decreased at post-stroke compared with that of pre-stroke.
  
  
  CONCLUSIONS
  Continuous ingestion of green tea catechins from an early age prevented the development of spontaneous stroke in M-SHRSP, probably by inhibiting the further development of high blood pressure at later ages.
authors.affiliation: College of Environment and Disaster Research, Fuji Tokoha University, Ohbuchi, Fuji, Shizuoka, Japan. masa@fuji-tokoha-u.ac.jp
authors.forename: Masahiko
authors.initials: M
authors.lastname: Ikeda
authors.forename: Chinatsu
authors.initials: C
authors.lastname: Suzuki
authors.forename: Keizo
authors.initials: K
authors.lastname: Umegaki
authors.forename: Kieko
authors.initials: K
authors.lastname: Saito
authors.forename: Masaki
authors.initials: M
authors.lastname: Tabuchi
authors.forename: Takako
authors.initials: T
authors.lastname: Tomita
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D028241:Camellia sinensis; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology; D006339:Heart Rate / Q000187:drug effects; D006973:Hypertension / Q000517:prevention & control; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D009566:Nitrates / Q000097:blood; D009573:Nitrites / Q000097:blood; D051381:Rats; D011918:Rats, Inbred SHR; D020521:Stroke / Q000517:prevention & control*
chemical_list: D009566:Nitrates; D009573:Nitrites; D002392:Catechin; C472086:polyphenon E