title: [Effects of intermittent artificial gravity on femur of simulated weightlessness rats].
abstract: OBJECTIVE
  To explore the effects of three intermittent artificial gravity on simulated weightlessness rats.
  
  
  METHODS
  30 male SD rats were divided into 5 groups: control group (C), tail-suspension group (S) and standing group (G1), 1.5 G group (G2), 2.6 G (G3) group; randomly and equally. G groups were given 1 h/d standing, 1.5 G or 2.6 G artificial gravity each day. The effects of 3 weeks artificial gravity on tail-suspension rats were evaluated by measuring physical and mechanical parameters of femur.
  
  
  RESULTS
  Compared to S rats, elastic ultimate load (EUL), the ultimate load (UL) and bending rigidity coefficient (BRC) of G1 rats (P < 0.05) improved significantly; Diameter (P < 0.01), mass (dry) and density (P < 0.05), EUL and UL (P < 0.05) of G2 rats raised significantly; EUL and UL of G3 rats (P < 0.01) improved markedly.
  
  
  CONCLUSIONS
  By using intermittent artificial gravity, the mechanical parameters of weight loading bones of simulated weightlessness rats were all improved apparently, and the one using 1.5 G 1 h/d artificial gravity was the best.
authors.affiliation: Faculty of Aerospace Medicine, Fourth Military Medical University, Xi'an 710032, China.
authors.forename: X S
authors.initials: XS
authors.lastname: Cao
authors.forename: X Y
authors.initials: XY
authors.lastname: Wu
authors.forename: Y H
authors.initials: YH
authors.lastname: Wu
authors.forename: B
authors.initials: B
authors.lastname: Sun
authors.forename: L N
authors.initials: LN
authors.lastname: Zhang
authors.forename: L F
authors.initials: LF
authors.lastname: Zhang
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D005269:Femur / Q000502:physiology*; D018470:Gravity, Altered; D008297:Male; D011187:Posture / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D016474:Weight-Bearing; D018474:Weightlessness Simulation