title: Effect of parathyroid hormone on hypogonadism induced bone loss of proximal femur of orchiectomized rat.
abstract: OBJECTIVE
  Management of hypogonadism-induced osteoporosis in elderly men is still a challenge. We investigated the short-term effects of parathyroid hormone (PTH) treatments on strength, micro-architecture, and mineral density of trochanteric region of orchiectomized rat femur.
  
  
  METHODS
  Eight-month-old male Sprague-Dawley rats (n = 44) were divided into two groups: (1) orchiectomized (ORX) and (2) sham group. Twelve weeks after orchiectomy, half of the orchiectomized animals were treated with daily subcutaneously injected PTH (0.040 mg/kg/BW) (ORX-PTH) for 5 weeks. The other half remained untreated (ORX). The sham-operated group was divided and treated in the same way (sham, sham-PTH). After 5 weeks, both femurs were excised for biomechanical and histomorphometric analysis, trabecular measurements, mineral content assessment, and immunofluorescence analysis.
  
  
  RESULTS
  The femoral trochanteric strength after PTH treatment was enhanced in the breaking test (ORX-F(max) = 158.7 N vs. ORX + PTH-F(max) = 202 N). Stiffness of treated ORX animals reached nearly the levels observed in untreated sham rats. PTH therapy improved the trabecular connectivity, width, and area (ORX-Tb.Ar = 47.79% vs. ORX + PTH-Tb.Ar = 68.47%, P < 0.05) in the proximal femur. The treated rats showed significantly improved mineral content in ashed femurs (ORX-mineral content = 43.73% vs. ORX + PTH-mineral content = 49.49%) when compared to the untreated animals. A comparison of widths of fluorescence bands in cortical bone of the subtrochanteric cross-sections showed a significant increase in oppositions after the PTH therapy.
  
  
  CONCLUSIONS
  Our finding supports the hypothesis that PTH therapy seems to be a rational therapy in patients with hypogonadism induced bone loss and improves the bone strength of trochanteric region of rat femur.
authors.affiliation: Department of Trauma and Reconstructive Surgery, Georg-August-University of Goettingen, Robert Koch Street 40, 37075, Goettingen, Germany. mtezval@med.uni-goettingen.de
authors.forename: M
authors.initials: M
authors.lastname: Tezval
authors.forename: G
authors.initials: G
authors.lastname: Serferaz
authors.forename: T
authors.initials: T
authors.lastname: Rack
authors.forename: L
authors.initials: L
authors.lastname: Kolios
authors.forename: S
authors.initials: S
authors.lastname: Sehmisch
authors.forename: U
authors.initials: U
authors.lastname: Schmelz
authors.forename: H
authors.initials: H
authors.lastname: Tezval
authors.forename: K M
authors.initials: KM
authors.lastname: Stuermer
authors.forename: E K
authors.initials: EK
authors.lastname: Stuermer
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena / Q000187:drug effects / Q000502:physiology; D001835:Body Weight / Q000187:drug effects / Q000502:physiology; D015519:Bone Density / Q000187:drug effects / Q000502:physiology; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D005269:Femur / Q000187:drug effects / Q000473:pathology / Q000503:physiopathology*; D007006:Hypogonadism / Q000150:complications*; D007279:Injections, Subcutaneous; D008297:Male; D009919:Orchiectomy; D010024:Osteoporosis / Q000188:drug therapy* / Q000209:etiology* / Q000503:physiopathology; D010281:Parathyroid Hormone / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D010281:Parathyroid Hormone