G protein-coupled receptor signalling in in vivo cardiac overload

Cardiac myocytes respond to biomechanical stress by initiating cellular pro cesses that lead to hypertrophy. Although cardiac hypertrophy is a response to increased stress on the heart, it is associated with elevated plasma ca techolamine levels and an increase in cardiac morbidity and mortality. Unde rstanding the cellular signals that initiate the hypertrophic response will be of critical importance to identify pathways that mediate the maladaptiv e deterioration of the hypertrophic heart to one of cardiac failure. This r eview will focus on the role of G protein-coupled receptors in the activati on of signalling pathways in the heart, such as the mitogen activated prote in kinase and phosphoinositide-3 kinase pathways.