[Effects of androgen on microstructure and mechanics nature of bone in orchiechtomied male rats].
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.
Dai
Hong-Bin
HB
Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital Affiliated to Shanghai Jiaotong University, Shanghai 200025, China.
Du
Ning
N
Lin
Kai-Ze
KZ
Jiang
Shui-Ming
SM
Zhang
Wei-Bin
WB
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
D000728:Androgens