ADIPOR1 and pulmonary arterial hypertension: Several studies have also reported an increase in adiponectin levels inPAH patients rather than a reduction confounding its role in PAH.63,64 Insulinresistance is prevalent in PAH patients, and elevated levels of insulin havebeen shown to downregulate AdipoR1/R2 expression limiting adiponectin’sphysiological effect and resulting in adiponectin resistance.65 Therefore, the increased circulating levels of adiponectin in PAH may bea result of the efforts of adipose tissues to prevent adiponectin functionalresistance.