title: [Effects of extracts of Radix Scrophulariae on blood pressure in spontaneously hypertensive rats and the underlying mechanisms].
abstract: OBJECTIVE
  To explore the effects of extracts of Radix Scrophulariae (ERS) on blood pressure, vasoconstrictors and morphology of artery in spontaneously hypertensive rats (SHRs).
  
  
  METHODS
  Fifty SHRs were randomly divided into SHR, SHR plus 40 mg/kg of captopril, SHR plus 70 mg/kg of ERS, SHR plus 140 mg/kg of ERS and SHR plus 280 mg/kg of ERS groups. Wistar-Kyoto (WKY) rats were randomly divided into two groups, namely, WKY and WKY plus 140 mg/kg of ERS groups. The rats were orally administered with the corresponding drugs or drinking water once a day for 20 weeks. The blood pressure was determined every three weeks. At the 21st week, the concentrations of noradrenaline (NA), angiotensin II (Ang II), thromboxane B(2) (TXB(2)) and 6-keto-prostaglandin F(1α) in serum and endothelin-1 (ET-1) were detected by enzyme-linked immunosorbent assay. The morphological changes in abdominal aorta were observed under an optical microscope with hematoxylin and eosin staining. The ratio of intima-media thickness/lumen radius of abdominal aorta was calculated.
  
  
  RESULTS
  ERS significantly lowered the blood pressure of SHRs from the 3rd to the 21st week; ERS also reduced the levels of NA, Ang II, ET-1 and TXB(2), decreased the intima-media thickness of abdominal aortal wall and improved the morphological changes in abdominal aorta in SHRs. In addition, ERS did not significantly change blood pressure and vasoactive substances in WKY rats.
  
  
  CONCLUSIONS
  ERS possesses beneficial effects in inhibiting hypertension and attenuating arteriosclerosis. The underlying mechanism may be associated with restraining the release of vasoconstrictors, such as NA, Ang II, ET-1 and TXB(2).
authors.affiliation: Department of Pharmacology, Shanghai University of Traditional Chinese Medicine, Shanghai, China. chenchantwins@hotmail.com
authors.forename: Chan
authors.initials: C
authors.lastname: Chen
authors.forename: Chang-xun
authors.initials: CX
authors.lastname: Chen
authors.forename: Xi-min
authors.initials: XM
authors.lastname: Wu
authors.forename: Rui
authors.initials: R
authors.lastname: Wang
authors.forename: Yi-ming
authors.initials: YM
authors.lastname: Li
mesh_terms: D015121:6-Ketoprostaglandin F1 alpha / Q000097:blood; D000804:Angiotensin II / Q000097:blood; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D004365:Drugs, Chinese Herbal / Q000627:therapeutic use*; D019332:Endothelin-1 / Q000032:analysis; D006973:Hypertension / Q000188:drug therapy* / Q000503:physiopathology*; D008297:Male; D009638:Norepinephrine / Q000097:blood; D008517:Phytotherapy; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D032266:Scrophularia / Q000737:chemistry; D013929:Thromboxane B2 / Q000097:blood
chemical_list: D004365:Drugs, Chinese Herbal; D019332:Endothelin-1; D000804:Angiotensin II; D013929:Thromboxane B2; D015121:6-Ketoprostaglandin F1 alpha; D009638:Norepinephrine