F2R and systemic lupus erythematosus: Methods: We measured the plasma levels of PAR1 and endothelin 1 in patients with membranous nephropathy (n = 19), focal and segmental glomerulosclerosis (FSGS) (n = 30), systemic lupus erythematosus (SLE) (n = 22), IgA nephropathy (n = 16), mesangial proliferative (non-IgA) glomerulonephritis (n = 7), chronic kidney disease (CKD) (n = 27), and hemodialysis (n = 26), as well as a healthy control group (n = 22).