There is evidence that the BMPR2 signaling pathway is disrupted in the case of polycystic ovary syndrome, possibly by hyperaldosterism. It appears that the hormones estrogen and follicle stimulating hormone (FSH) have roles in regulating expression of BMPR2 in granulosa cells. Experimental treatment in animal models with estradiol with or without FSH increased BMPR2 mRNA expression while treatment with FSH alone decreased BMPR2 expression. However, in human granulosa-like tumor cell line (KGN), treatment with FSH increased BMPR2 expression. An inactivating mutation in the "BMPR2" gene has been linked to pulmonary arterial hypertension. BMPR2 functions to inhibit the proliferation of vascular smooth muscle tissue. It functions by promoting the survival of pulmonary arterial endothelial cells, therefore preventing arterial damage and adverse inflammatory responses. It also inhibits pulmonary arterial proliferation in response to growth factors, which prevents the closing of arteries by proliferating endothelial cells. When this gene is inhibited, vascular smooth muscle proliferates and can cause pulmonary hypertension, which, among other things, can lead to cor pulmonale, a condition that causes the right side of the heart to fail. The dysfunction of BMPR2 can also lead to an elevation in pulmonary arterial pressure due to an adverse response of the pulmonary circuit to injury. It is especially important to screen for BMPR2 mutations in relatives of patients with idiopathic pulmonary hypertension, for these mutations are present in >70% of familial cases. There have been studies which has correlated BMPR2 with exercise induced elevation of PA pressure by measuring tricuspid regurgitation velocity by echocardiography.