Transforming growth factor beta-1 modulates the number of beta-adrenergic receptors in cardiac fibroblasts

J Mol Cell Cardiol. 1994 Apr;26(4):435-40. doi: 10.1006/jmcc.1994.1054.


The effects of transforming growth factor beta-1 on concentration of intracellular Ca2+ changes in the presence of isoproterenol were studied in cardiac fibroblasts. Transforming growth factor beta-1 effect on cyclic-AMP production and ligand assay of beta-adrenergic receptors were also examined. Production of cyclic-AMP in fibroblasts preincubated with transforming growth factor beta-1 decreased compared with non-transforming growth factor beta-1-treated fibroblasts in the presence of isoproterenol. An increase of intracellular Ca2+ concentration in the presence of isoproterenol was also inhibited in transforming growth factor beta-1-treated fibroblasts. Islet-activating protein did not restore these reactions of transforming growth factor beta-1. Concentration change of intracellular calcium under the treatment of transforming growth factor beta-1 was unaffected by forskolin addition. Binding of [3H]CGP-12177 was decreased to 47% of control preincubated for 24 h with transforming growth factor beta-1 in fibroblasts. Scatchard plots suggested a decrease in beta-adrenergic receptor number without specific change in receptor affinity. These results suggested that transforming growth factor beta-1 modulates the signal transduction through beta-adrenergic receptor and intracellular Ca2+ concentration by regulating the number of receptor in fibroblasts.

MeSH terms

  • Animals
  • Calcium / analysis
  • Calcium / metabolism
  • Cells, Cultured
  • Colforsin / pharmacology
  • Cyclic AMP / analysis
  • Cyclic AMP / metabolism
  • Fibroblasts / chemistry*
  • Fibroblasts / metabolism
  • Fibroblasts / ultrastructure
  • Isoproterenol / pharmacology
  • Myocardium / cytology*
  • Myocardium / metabolism
  • Rats
  • Rats, Wistar
  • Receptors, Adrenergic, beta / analysis*
  • Receptors, Adrenergic, beta / metabolism
  • Receptors, Adrenergic, beta / physiology
  • Signal Transduction / drug effects
  • Signal Transduction / physiology
  • Transforming Growth Factor beta / pharmacology*


  • Receptors, Adrenergic, beta
  • Transforming Growth Factor beta
  • Colforsin
  • Cyclic AMP
  • Isoproterenol
  • Calcium