Propranolol and verapamil inhibit mRNA expression of RyR2 and SERCA in L-thyroxin-induced rat ventricular hypertrophy
Abstract
AIM:
To study the alteration in the mRNA level of cardiac ryanodine receptor 2 (RyR2) and sarco-endoplasmic reticulum Ca2+-ATPase (SERCA) in L-thyroxin-induced hypertrophy.
METHODS:
L-thyroxin (500 g/kg) daily was injected for 10 d. RT-PCR was used to determine mRNA expression.
RESULTS:
An increase in the relative amount of RyR2 (111 %) and SERCA mRNA (65 %) expression was observed in the hypertrophied rats (RyR2: 77+/-11; SERCA: 87+/-10, n=9) compared with the normal rats (RyR2: 36+/-10; SERCA: 53+/-10, n=9). Propranolol was effective to inhibit the increase in RyR2 (51+/-7) and SERCA (63+/-13) mRNA expression in hypertrophied rats, respectively. Verapamil also reduced RyR2 (62+/-5) and SERCA (75+/-8) mRNA expression.
CONCLUSION:
Both RyR2 and SERCA mRNA level in L-thyroxin-induced cardiac hypertrophy was over-expressed and propranolol or verapamil inhibited the alteration.
Keywords:
To study the alteration in the mRNA level of cardiac ryanodine receptor 2 (RyR2) and sarco-endoplasmic reticulum Ca2+-ATPase (SERCA) in L-thyroxin-induced hypertrophy.
METHODS:
L-thyroxin (500 g/kg) daily was injected for 10 d. RT-PCR was used to determine mRNA expression.
RESULTS:
An increase in the relative amount of RyR2 (111 %) and SERCA mRNA (65 %) expression was observed in the hypertrophied rats (RyR2: 77+/-11; SERCA: 87+/-10, n=9) compared with the normal rats (RyR2: 36+/-10; SERCA: 53+/-10, n=9). Propranolol was effective to inhibit the increase in RyR2 (51+/-7) and SERCA (63+/-13) mRNA expression in hypertrophied rats, respectively. Verapamil also reduced RyR2 (62+/-5) and SERCA (75+/-8) mRNA expression.
CONCLUSION:
Both RyR2 and SERCA mRNA level in L-thyroxin-induced cardiac hypertrophy was over-expressed and propranolol or verapamil inhibited the alteration.