The TRPM subfamily of mammalian TRP channels includes TRPM4, which is a Ca2+-activated nonselective cation channel that mediates cell membrane depolarisation []. Unlike TRPM5, its closest relative in the transient receptor potential family, TRPM4 proteins are widely expressed in the body []. They are abundant expressed in cardiac cells and are involved in several aspects of cardiac rhythmicity, including cardiac conduction, pace making and action-potential repolarisation []. They are also expressed in cerebral arteries, where they play a role in myogenic vasoconstriction []. TRPM4 proteins also affect T-helper 1 (Th1) and T-helper 2 (Th2) cell motility and cytokine production through differential regulation of calcium signalling and NFATC1 localisation [].
