Z Cui1, W Chang, X Chen, L Chen, L Liu. 1. Department of Biochemistry, Fu Wai Hospital, CAMS and PUMC, Beijing 100037.
Abstract
OBJECTIVE: To clarify the effect of cAMP on the transcription of angiotensin II type 1 (AT1) receptor mRNA in cardiomyocytes. METHODS: Cardiomyocytes from SD neonatal rats were cultured in DMEM containing 10% fetal bovine serum (FBS) with 0.1 mmol/L 5-bromodeoxyuridine (Brdu). At day 5-7, primary cultured cells were used. FBS and Brdu were deprived 24 h before the stimulation. The levels of AT1 mRNA in primary cultured cardiomyocytes were examined by RT-PCR. RESULTS: Stimulation of forskolin (30 mumol/L) plus 3-isobutyl-1-methyl-xanthine (IBMX, 30 mumol/L) which induced the accumulation of cellular cAMP decreased the expression of AT1 receptor mRNA to (64.4 +/- 20.3)% of control at 6 h treatment; while it increased the expression of AT1 receptor mRNA to (209.6 +/- 24.0)% of control at 48 h treatment. CONCLUSIONS: cAMP regulated the transcription of AT1 receptor gene.
OBJECTIVE: To clarify the effect of cAMP on the transcription of angiotensin II type 1 (AT1) receptor mRNA in cardiomyocytes. METHODS: Cardiomyocytes from SD neonatal rats were cultured in DMEM containing 10% fetal bovine serum (FBS) with 0.1 mmol/L 5-bromodeoxyuridine (Brdu). At day 5-7, primary cultured cells were used. FBS and Brdu were deprived 24 h before the stimulation. The levels of AT1 mRNA in primary cultured cardiomyocytes were examined by RT-PCR. RESULTS: Stimulation of forskolin (30 mumol/L) plus 3-isobutyl-1-methyl-xanthine (IBMX, 30 mumol/L) which induced the accumulation of cellular cAMP decreased the expression of AT1 receptor mRNA to (64.4 +/- 20.3)% of control at 6 h treatment; while it increased the expression of AT1 receptor mRNA to (209.6 +/- 24.0)% of control at 48 h treatment. CONCLUSIONS:cAMP regulated the transcription of AT1 receptor gene.