title: Modulation of type beta transforming growth factor activity in bone cultures by osteotropic hormones.
abstract: Type beta transforming growth factor (TGF-beta) activity was found in conditioned medium harvested from fetal rat and neonatal mouse calvariae by using the anchorage-independent growth of normal rat kidney fibroblasts as an indicator system. Calvariae incubated with parathyroid hormone, 1,25-dihydroxyvitamin D3, and interleukin 1, all factors that stimulate bone resorption showed a concentration-dependent increase in TGF-beta activity in the culture medium. Increases in TGF-beta activity persisted undiminished for 48 hr after removal of these factors. The increases in TGF-beta activity from the resorbing bone cultures were relatively greater than the increases in bone resorption. Calcitonin inhibition of bone resorption correlated with a decrease in TGF-beta activity. Thus, agents that modulate bone resorption also affect TGF-beta activity in the bone culture medium. Changes in local concentrations of TGF-beta activity by osteotropic hormones may be important in the regulation of normal bone remodeling.
mesh_terms: D000818:Animals; D001862:Bone Resorption / Q000187:drug effects; D001842:Bone and Bones / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D002116:Calcitonin / Q000494:pharmacology; D002117:Calcitriol / Q000494:pharmacology; D002460:Cell Line; D002478:Cells, Cultured; D004815:Epidermal Growth Factor / Q000494:pharmacology; D005333:Fetus; D006133:Growth Substances / Q000096:biosynthesis* / Q000378:metabolism / Q000494:pharmacology*; D006728:Hormones / Q000494:pharmacology*; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology; D007668:Kidney; D007700:Kinetics; D051379:Mice; D010281:Parathyroid Hormone / Q000494:pharmacology; D010452:Peptide Biosynthesis; D010446:Peptide Fragments / Q000494:pharmacology; D010455:Peptides / Q000378:metabolism; D051381:Rats; D011994:Recombinant Proteins / Q000494:pharmacology; D019379:Teriparatide; D015291:Transforming Growth Factors
chemical_list: D006133:Growth Substances; D006728:Hormones; D007375:Interleukin-1; D010281:Parathyroid Hormone; D010446:Peptide Fragments; D010455:Peptides; D011994:Recombinant Proteins; D019379:Teriparatide; D004815:Epidermal Growth Factor; D015291:Transforming Growth Factors; D002116:Calcitonin; D002117:Calcitriol