Recent insights on the role of TRP channels in cardiac muscle

The human TRP protein family comprises a family of 27 cation channels with diverse permeation and gating properties. The common theme is that they are very important regulators of intracellular Ca 2+ signalling in diverse cell types, either by providing a Ca 2+ influx pathway, or by depolarising the membrane potential, which on one hand triggers the activation of voltage-gated Ca 2+ channels, and on the other limits the driving force for Ca 2+ entry. Several TRP channels are implicated in function and regulation of the heart. Aspects include the regulation of contractile strength, pacemaking, (regulation of) growth and proliferation, and the risk for developing rhythm disorders. Moreover, some TRP channels have been implicated in heritable cardiac disorders and acquired diseases. This review provides a comprehensive and critical overview of these findings, with an emphasis on recent findings from genetically modified mouse models.