title: [Effects of parathyroid hormone on osteoprotegerin expression and osteoprotegerin ligand and their related cytokines in human osteoblasts].
abstract: OBJECTIVE
  To investigate the pathway and mechanism of parathyroid hormone (PTH) in regulating bone resorption.
  
  
  METHODS
  We observed the regulative effects of PTH on the expression of osteoprotegerin (OPG) and osteoprotegerin ligand (OPGL) and their related cytokines (M-CSF and TRAIL) in human osteoblasts (HOBs). The expressions of OPG, OPGL, M-CSF, and TRAIL mRNA were determined by RT-PCR. The expressions of OPG and OPGL proteins were measured by Western blotting.
  
  
  RESULTS
  PTH down-regulated the expression of OPG but up-regulated the expressions of OPGL, M-CSF and TRAIL in HOBs.
  
  
  CONCLUSIONS
  PTH can promote the bone resorption by decreasing the expression of OPG, increasing the expressions of some bone-resorbing cytokines such as OPGL, M-CSF, and TRAIL in osteoblasts, and then stimulating the osteoclast differentiation and activity.
authors.affiliation: Institute of Endocrinology and Metabolism, Second Xiangya Hospital, Central South University, Changsha 410011, China. suxin@21cn.com
authors.forename: Xin
authors.initials: X
authors.lastname: Su
authors.forename: Er-yuan
authors.initials: EY
authors.lastname: Liao
authors.forename: Jian
authors.initials: J
authors.lastname: Peng
authors.forename: Shi-ping
authors.initials: SP
authors.lastname: Liu
authors.forename: Ru-chun
authors.initials: RC
authors.lastname: Dai
mesh_terms: D002478:Cells, Cultured; D016207:Cytokines / Q000096:biosynthesis* / Q000235:genetics; D006801:Humans; D016173:Macrophage Colony-Stimulating Factor / Q000096:biosynthesis / Q000235:genetics; D010006:Osteoblasts / Q000166:cytology / Q000378:metabolism*; D053244:Osteoprotegerin / Q000096:biosynthesis* / Q000235:genetics; D010281:Parathyroid Hormone / Q000494:pharmacology*; D053245:RANK Ligand / Q000096:biosynthesis* / Q000235:genetics; D053221:TNF-Related Apoptosis-Inducing Ligand / Q000096:biosynthesis / Q000235:genetics
chemical_list: D016207:Cytokines; D053244:Osteoprotegerin; C470125:PTH protein, human; D010281:Parathyroid Hormone; D053245:RANK Ligand; D053221:TNF-Related Apoptosis-Inducing Ligand; C505653:TNFSF10 protein, human; D016173:Macrophage Colony-Stimulating Factor