title: Elcatonin attenuates disuse osteoporosis after fracture fixation of tubular bone in rats.
abstract: BACKGROUND
  Elcatonin (ECT) is used to prevent and treat osteoporosis. However, little is known about its effect on the disuse osteoporosis (DOP). The aim of this study is to evaluate the effect of ECT on DOP caused by fracture fixation.
  
  
  METHODS
  Forty-five male Sprague-Dawley (SD) rats, aged 6 weeks, were randomly allocated into three groups: the control group without surgery and elcatonin treatment (CTR, n = 15), the surgery group without elcatonin treatment (SUR, n = 15), and the surgery group which received elcatonin subcutaneously (SUR + ECT, n = 15). Surgery was produced by cutting the midshaft of the right femur transversely, fixing with stainless intramedullary needle, and immobilizing the right leg. All the proximal tibias from the random five rats in each group were harvested and investigated by evaluating bone mineral density (BMD), X-ray images, and histological staining respectively at the 4th, 8th, and 12th weeks after surgery.
  
  
  RESULTS
  Both of the SUR and SUR + ECT groups obviously exhibited lower BMD values compared to the CTR group; however, the SUR + ECT group showed significantly higher BMD values (p < 0.001, p < 0.05, and p < 0.05) than the SUR group at each time point after surgery. Moreover, similar changes were observed between these groups when examining the radiographs and hematoxylin and eosin (HE) staining.
  
  
  CONCLUSIONS
  Elcatonin attenuates disuse osteoporosis after fractures in rats, which may provide a new avenue to prevent and treat disuse osteoporosis after surgery in clinic.
authors.affiliation: Department of Orthopaedics, The Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi Province, 710004, People's Republic of China. zhej23@163.com.
authors.forename: Zhe
authors.initials: Z
authors.lastname: Ji
authors.affiliation: Department of Orthopaedics, The Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi Province, 710004, People's Republic of China. xjtumed2009@163.com.
authors.forename: Chao
authors.initials: C
authors.lastname: Shi
authors.affiliation: Department of Orthopaedics, The Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi Province, 710004, People's Republic of China. hstudent@163.com.
authors.forename: Shengli
authors.initials: S
authors.lastname: Huang
authors.affiliation: Department of Orthopaedics, The Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi Province, 710004, People's Republic of China. dangxiaoqian@vip.163.com.
authors.forename: Xiaoqian
authors.initials: X
authors.lastname: Dang
authors.affiliation: Department of Orthopaedics, The Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi Province, 710004, People's Republic of China. wkzh1955@163.com.
authors.forename: Kunzheng
authors.initials: K
authors.lastname: Wang
authors.affiliation: Department of Orthopaedics, The Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi Province, 710004, People's Republic of China. bslan56@163.com.
authors.forename: Binshang
authors.initials: B
authors.lastname: Lan
mesh_terms: D000818:Animals; D015519:Bone Density; D001842:Bone and Bones / Q000000981:diagnostic imaging / Q000473:pathology; D002116:Calcitonin / Q000031:analogs & derivatives* / Q000627:therapeutic use; D004353:Drug Evaluation, Preclinical; D005592:Fracture Fixation / Q000009:adverse effects*; D008297:Male; D010024:Osteoporosis / Q000209:etiology / Q000473:pathology / Q000517:prevention & control*; D011859:Radiography; D011897:Random Allocation; D017207:Rats, Sprague-Dawley
chemical_list: D002116:Calcitonin; C012755:elcatonin