title: Protective effect of Tianqi Hangli Recipe () extract on high sustained positive acceleration stress-induced myocardial mitochondrial injury in rats.
abstract: OBJECTIVE
  To explore the protective effect of Tianqi Hangli Recipe () extract (THRE) on high sustained positive acceleration (+Gz) stress-induced myocardial mitochondrial injury in rats.
  
  
  METHODS
  Seventy-two male SD rats were randomly assigned to various groups with 12 rats per group: blank control group, stress control group, high +Gz stress group, low-dose THRE group (0.75 g/kg), medium-dose THRE group (1.5 g/kg) and high dose THRE group (3.0 g/kg). Each rat was fifi rstly fed with 20 mL/kg menstruum once a day for 14 days. The rats were then exposed to high +Gz at the 15th day. Myocardial mitochondrial structure, respiratory function, antioxidant capacity and ATPases activities were examined for the comparison after the high +Gz exposure.
  
  
  RESULTS
  The rats treated with high +Gz stress showed signififi cant pathological changes: the myocardial mitochondria were swelled, degenerated and decreased, and mitochondrial cristae were broken or disappeared. State 3 respiration and the respiratory control ratio (RCR) were both significantly lower, and state 4 respiration was higher as compared with the blank control group and stress control groups (P <0.01, P <0.05). In addition, the activities of its antioxidant enzymes [superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px)] and Na+-K+-ATPase were also decreased (P <0.01 or P <0.05), but the formation of malondialdehyde (MDA) was increased (P <0.01). However, THRE preconditioning could attenuate mitochondrial structural damages and reverse the high +Gz stress-caused changes of parameters about respiration, antioxidant enzymes and ATPases, most of which had no significant difference between the high-dose THRE group and the stress control group.
  
  
  CONCLUSIONS
  THRE can protect high sustained +Gz stress-induced myocardial mitochondrial injury in rats as was shown to ameliorate respiratory function and increase activities of antioxidant enzymes and ATPases.
authors.affiliation: Institute of Aviation Medicine, Air Force, Beijing, 100142, China.
authors.forename: Liang-En
authors.initials: LE
authors.lastname: Chen
authors.forename: Feng
authors.initials: F
authors.lastname: Wu
authors.forename: Yi-Mei
authors.initials: YM
authors.lastname: Xin
authors.forename: An-Dong
authors.initials: AD
authors.lastname: Zhao
authors.forename: Yong-Xin
authors.initials: YX
authors.lastname: Wang
authors.forename: Hao
authors.initials: H
authors.lastname: Zhan