TRPC6 and pulmonary arterial hypertension: The relevance of TRPC6 channels for HPV is further supported by the fact that siRNA-mediated downregulation of TRPC6 expression inhibits the proliferation of PASMCs (Yu et al., 2003), while single nucleotide mutations of the Trpc6 gene are associated with idiopathic pulmonary hypertension (Yu et al., 2009).