title: [Quantification of mRNA expression for angiotensinogen in rat arterial tissues by real-time PCR].
abstract: OBJECTIVE
  To develop a real-time PCR method for quantifying low abundance mRNA expression in rat arterial tissues and examine differential changes of angiotensinogen (AGT) gene expression in basilar and femoral arterial tissues after 8 weeks simulated weightlessness.
  
  
  METHODS
  After 8-wk of simulation, basilar and femoral arteries were harvested from both simulated weightless (SUS) and control (CON) rats. Then total RNA was extracted and reverse transcribed. The real-time PCR using TaqMan-MGB probe was performed to quantify AGT mRNA expression. The amplification efficiency (E) of PCR was calculated from the slope of standard curve. The threshold cycle (Ct) was detected by changes in fluorescence during a real-time PCR. Finally, the relative expression ratio of the target gene (AGT) to the reference gene (GAPDH) was calculated using E and Ct according to the mathematical model derived from the equation calculating the starting fluorescence (Ro).
  
  
  RESULTS
  After a 8-weeks simulated weightlessness, the AGT mRNA expression increased by 240 percent in basilar arterial, and decreased by 66 percent in femoral arterial tissues.
  
  
  CONCLUSIONS
  The specificity, sensitivity, precision, reproducibility, and simplicity of real-time PCR method using TaqMan-MGB probe make it particularly suitable for quantification of low abundance mRNA in arterial tissue from rats.
authors.affiliation: Department of Aerospace Physiology, Fourth Military Medical University, Xi'an 710032, China.
authors.forename: Jun-xiang
authors.initials: JX
authors.lastname: Bao
authors.forename: Jin-rong
authors.initials: JR
authors.lastname: Zhao
authors.forename: Yu-jie
authors.initials: YJ
authors.lastname: Bai
authors.forename: Li-fan
authors.initials: LF
authors.lastname: Zhang
mesh_terms: D000808:Angiotensinogen / Q000235:genetics* / Q000378:metabolism; D000818:Animals; D001808:Blood Vessels / Q000378:metabolism*; D015870:Gene Expression; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D060888:Real-Time Polymerase Chain Reaction; D015203:Reproducibility of Results; D018474:Weightlessness Simulation
chemical_list: D012333:RNA, Messenger; D000808:Angiotensinogen