| Cardiac hypertrophy is an adaptive response of the heart to virtually all forms of cardiac diseases, including those arising from hypertension, mechanical load, myocardial infarction, cardiac arrhythmias, endocrine disorders, and genetic mutations in cardic contractile protein genes. While the hypertrophic response is initially a compensatory mechanism that augments cardiac output, hypertrophy can lead to dilated cardiomyopathy, heart failure, and sudden death. Cardiac hypertrophy was an absolute and dangerous factor that affected mortality and morbidity of cardiovascular diseases.Numerous studies have implicated intracellular [Ca2+]i as a signal for cardiac hypertrophy. It is indicated that Ca2+ signals play a central role in the development of cardiac hypertrophic growth and gene expression.The humoral factors, including angiotensinâ…¡(Angâ…¡),adrenaline (AD) and endothelin-1(ET-1), induce the hypertrophic response in cardiomyocytes, also share the ability to elevate intracellular Ca2+ concentrations. Increasing evidences suggest that Angâ…¡may act as a growth factor for the heart through Gq protein-coupled receptors. Angâ…¡activates multiple phospholipases, including phospholipase C ( PLC ) , through binding AT1 receptor in cardiac myocytes. Activation of PLC leads to production of inositol trisphosphate (IP3) and diacylglycerol (DAG) through hydrolysis of phosphatidylinositol 4, 5-disphosphate (PIP2). These second messengers are known to cause release of Ca2+ from intracellular stores and activation of protein kinase C (PKC). It is known that Angâ…¡not only increases Ca2+ influx through the L-type Ca2+ channel but also induces Ca2+ release from intracellular Ca2+ stores. Ca2+ may be an important factor in Angâ…¡-mediated growth.Nowadays, angiotensin converting enzyme inhibitor and calcium channel blockers are mainly used for curing cardiac hypertrophy. Some calcium channel blockers had satisfactory anti-hypertrophy effect. So, it would have...
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