title: [Effects of androgen on microstructure and mechanics nature of bone in orchiechtomied male rats].
abstract: OBJECTIVE
  To investigate the effect of androgen on microstructure and mechanics nature of bone in orchiechtomied (ORX) male rats and reveal its mechanism by using the Micro CT analysis, bone biomechanics test, bone histomorphometric parameter test, and total body bone mineral density (BMD) measured by dual-energy X-ray absorptiomery (DXA).
  
  
  METHODS
  Thirty 12-month-old male Wister rats were randomly divided into three groups including ORX, sham-operated (Sham) and androgen (AD) group, ten rats in every group. Total body BMD was measured by DXA. Femurs and vertebrae were then harvested at the 12 th week after ORX for micro-computed tomography (Micro CT), histology and biomechanical were tested.
  
  
  RESULTS
  The administration of testosterone may reverse the decreasing BMD of total body and may prevent the decreasing weight. The biomechanical values of Maximum load, Enery, Maximum stress, Elastic Modulus of AD group significantly enhanced compared with ORX group (P < 0.05). The results of histomorphometric parameters showed that cancellous bone volume, osteoblast-osteoid interface, linear extent of bone formation, mineralizing surfaces, mineral apposition rate increased in the therapy group.
  
  
  CONCLUSIONS
  Androgen can accelerate cancellous bone formation and bone turnover, improve bone microstructure and enhance bone intensity and BMD.
authors.affiliation: Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital Affiliated to Shanghai Jiaotong University, Shanghai 200025, China.
authors.forename: Hong-Bin
authors.initials: HB
authors.lastname: Dai
authors.forename: Ning
authors.initials: N
authors.lastname: Du
authors.forename: Kai-Ze
authors.initials: KZ
authors.lastname: Lin
authors.forename: Shui-Ming
authors.initials: SM
authors.lastname: Jiang
authors.forename: Wei-Bin
authors.initials: WB
authors.lastname: Zhang
mesh_terms: D000728:Androgens / Q000494:pharmacology*; D000818:Animals; D001696:Biomechanical Phenomena; D001835:Body Weight / Q000187:drug effects; D015519:Bone Density / Q000187:drug effects; D001842:Bone and Bones / Q000187:drug effects* / Q000648:ultrastructure; D021621:Imaging, Three-Dimensional; D008297:Male; D009919:Orchiectomy; D010024:Osteoporosis / Q000209:etiology; D051381:Rats; D017208:Rats, Wistar
chemical_list: D000728:Androgens