Effect of transforming growth factor beta-1 on the intracellular calcium in cardiac fibroblasts.
We attempted to determine the effects of transforming growth factor beta-1 on intracellular Ca2+ concentration changes in the presence of isoproterenol in cardiac fibroblasts. Transforming growth factor beta-1 inhibited the increase of intracellular Ca2+ concentration in the presence of isoproterenol in fibroblasts. It also inhibited the production of cyclic-AMP in fibroblasts in the presence of isoproterenol. Islet-activating protein did not block these reactions of transforming growth factor beta-1. Forskolin did not affect the intracellular calcium concentration change resulting from treatment with transforming growth factor beta-1. Binding of [3H]CGP-12177 was decreased to 47% of control preincubated for 24 hours 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 receptors in fibroblasts.
Iizuka
K
K
Department of Cardiovascular Medicine, Hokkaido University School of Medicine, Sapporo, Japan.
Kawaguchi
H
H
Murakami
T
T
Kitabatake
A
A
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D000242:Cyclic AMP / Q000378:metabolism; D005347:Fibroblasts / Q000378:metabolism; D007545:Isoproterenol / Q000378:metabolism; D009206:Myocardium / Q000166:cytology* / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D011943:Receptors, Adrenergic, beta / Q000502:physiology; D015398:Signal Transduction; D016212:Transforming Growth Factor beta / Q000494:pharmacology*
D011943:Receptors, Adrenergic, beta; D016212:Transforming Growth Factor beta; D000242:Cyclic AMP; D007545:Isoproterenol; D002118:Calcium