title: Effect of rat brain tissue extracts on osteoblast proliferation and differentiation.
abstract: OBJECTIVE
  The reason for enhanced fracture healing in traumatic brain injury patients is not clearly understood. It is possible that factors inherent in the brain passing through the blood-brain barrier to the peripheral circulation, or a disruption of central nervous system (CNS) control of the sympathetic nervous system (SNS), stimulates the process of fracture healing.
  
  
  METHODS
  In this study, we assessed proliferation [using the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay] and differentiation [using alkaline phosphatase (ALP)] in rat osteoblasts incubated with gray matter or other tissue extracts with and without the addition of an α- or β-adrenergic receptor blocker (phentolamine or propranolol).
  
  
  RESULTS
  Gray matter extract from normal brain caused a dose-dependent increase in osteoblast proliferation and differentiation. Serum from normal rats enhanced differentiation but not proliferation. Alpha-receptor blockade had no effect on proliferation or differentiation. Beta-receptor blockade caused a partial, but statistically significant, decrease in gray matter stimulation of osteoblast differentiation.
  
  
  CONCLUSIONS
  The results of this study indicate that gray matter extract from normal brain increases osteoblast proliferation and differentiation and that β receptors may be involved in differentiation under these conditions.
authors.affiliation: Department of Orthopaedics, Huashan Hospital, Fudan University, 12 Wulumuqi Middle Road, Shanghai 200040, China.
authors.forename: Gang-Yong
authors.initials: GY
authors.lastname: Huang
authors.forename: Xin
authors.initials: X
authors.lastname: Ma
authors.forename: Xin-Lei
authors.initials: XL
authors.lastname: Xia
authors.forename: Jian-Yuan
authors.initials: JY
authors.lastname: Jiang
authors.forename: Wei-Fang
authors.initials: WF
authors.lastname: Jin
authors.forename: Jian-Jun
authors.initials: JJ
authors.lastname: Gao
authors.forename: Huang-Yuan
authors.initials: HY
authors.lastname: Huang
mesh_terms: D000433:1-Propanol / Q000494:pharmacology; D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology; D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn; D001921:Brain / Q000378:metabolism*; D001923:Brain Chemistry; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004336:Drug Antagonism; D005562:Formazans / Q000378:metabolism; D010006:Osteoblasts / Q000187:drug effects* / Q000378:metabolism; D010646:Phentolamine / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013778:Tetrazolium Salts / Q000378:metabolism; D014020:Tissue Extracts / Q000494:pharmacology*
chemical_list: D000317:Adrenergic alpha-Antagonists; D005562:Formazans; D013778:Tetrazolium Salts; D014020:Tissue Extracts; C079782:MTT formazan; D000433:1-Propanol; D000469:Alkaline Phosphatase; D010646:Phentolamine