title: [Effects of 7 d head-down tilt (-20 degrees) immobilization on pharmacokinetics of gentamicin in rabbits].
abstract: OBJECTIVE
  To observe pharmacokinetic changes under simulated weightlessness in relevant to body flood flow changes.
  
  
  METHODS
  Gentamicin was selected as probe drug in the present study, and rabbits exposed to Head-Down Tilt (HDT, -20 degrees) immobilization were selected as simulated weightlessness animal model. Seven rabbits were treated inf. with 3 mg/kg of gentamicin sulfate pre-HDT and 7 d after HDT. Gentamicin blood samples within 4 h after administration were analyzed by TDxFLx.
  
  
  RESULTS
  The distribution of gentamicin postponed significantly: a significant decrease in alpha from (0.1838 +/- 0.1076) min-1 before HDT to (0.0591 +/- 0.0334) min-1 after HDT; a significant increase in t1/2 alpha from (5.30 +/- 3.55) min to (15.04 +/- 7.49) min; a significant decrease in k12 from (0.1025 +/- 0.0721) min-1 to (0.0181 +/- 0.0161) min-1, a increase trend in V(C) and V(D). After HDT, CL(S) of gentamicin increased from (2.2 +/- 0.5) ml min-1 kg-1 to (2.7 +/- 0.3) ml min-1 kg-1.
  
  
  CONCLUSIONS
  Simulated weightlessness might induce pharmacokinetic changes.
authors.affiliation: Institute of Space Medico-Engineering, Beijing, China.
authors.forename: Z F
authors.initials: ZF
authors.lastname: Guo
authors.forename: J Y
authors.initials: JY
authors.lastname: Gao
authors.forename: B Z
authors.initials: BZ
authors.lastname: Wang
authors.forename: H Z
authors.initials: HZ
authors.lastname: Shi
authors.forename: J
authors.initials: J
authors.lastname: Wang
authors.forename: J K
authors.initials: JK
authors.lastname: Qian
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D000900:Anti-Bacterial Agents / Q000493:pharmacokinetics*; D018495:Fluid Shifts / Q000502:physiology*; D005839:Gentamicins / Q000493:pharmacokinetics*; D018475:Head-Down Tilt; D007103:Immobilization; D011817:Rabbits; D013997:Time Factors; D018474:Weightlessness Simulation
chemical_list: D000900:Anti-Bacterial Agents; D005839:Gentamicins