AGTR1 and hypertensive disorder: High levels of autoantibodies against the second extracellular loop of α1-adrenoceptor (α1-AR) are also found in patients with hypertension, suggesting an important role of α1-AR and AT(1)R autoimmunity in the pathogenesis and management of hypertension, particularly in patients having high levels of receptor-associated autoantibodies [11, 45, 46].