title: [Hypersensitization of alpha-adrenoreceptor of artery smooth muscle in hypertensive rats and hypertensive patients].
abstract: OBJECTIVE
  To investigate the hypersensitization of alpha-adrenoreceptor of artery smooth muscle in hypertensive patients and rats and the mechanisms concerned.
  
  
  METHODS
  Isometric tension of artery ring segments was recorded by a sensitive myograph system in vitro and the relative amount of alpha-adrenoreceptor mRNA was quantified by a real-time PCR.
  
  
  RESULTS
  Noradrenaline (NA)-induced concentration-contraction curve of mesenteric artery segments in spontaneously hypertensive rats (SHR) was more potent than that in Wistar-Kyoto (WKY) rats. The E(max) of NA in SHR was 1.82 times of that of WKY. The concentration-contractile curve induced by NA in great omental arteries of hypertensives significantly shifted toward left and the pD2 value of NA was larger than that of normotensives. After organ culture, the concentration-contractile curves of SD rat mesenteric artery induced by NA shifted toward left with significantly increased E(max). The relative amounts of mRNA for alpha1-adrenoreceptor was increased, but mRNA level for alpha2-adrenoreceptor did not change.
  
  
  CONCLUSIONS
  The sensitivity of alpha1-adrenoreceptor of artery smooth muscle in hypertensive man and rat is enhanced, suggesting alpha1-adrenoreceptor is upregulated.
authors.affiliation: Department of Pharmacology, School of Medicine, Xi'an Jiaotong University, Xi'an 710061, China. yxy@xjtu.edu.cn
authors.forename: Yong-Xiao
authors.initials: YX
authors.lastname: Cao
authors.forename: Jie
authors.initials: J
authors.lastname: Li
authors.forename: Hao
authors.initials: H
authors.lastname: Liu
authors.forename: Guo-Gang
authors.initials: GG
authors.lastname: Luo
mesh_terms: D000316:Adrenergic alpha-Agonists / Q000494:pharmacology; D000818:Animals; D004305:Dose-Response Relationship, Drug; D006801:Humans; D006973:Hypertension / Q000503:physiopathology*; D066298:In Vitro Techniques; D008638:Mesenteric Arteries / Q000187:drug effects / Q000378:metabolism / Q000503:physiopathology*; D009119:Muscle Contraction / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000378:metabolism / Q000503:physiopathology*; D009638:Norepinephrine / Q000494:pharmacology; D009852:Omentum / Q000098:blood supply; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D017207:Rats, Sprague-Dawley; D011942:Receptors, Adrenergic, alpha / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013045:Species Specificity; D014661:Vasoconstriction / Q000187:drug effects
chemical_list: D000316:Adrenergic alpha-Agonists; D012333:RNA, Messenger; D011942:Receptors, Adrenergic, alpha; D009638:Norepinephrine