Nebentan potassium inhibits the specific binding of [ ¹²⁵ I] endothelin-1 to endothelin ET _A and ET _B receptors in a concentration dependent manner, K _i values are 0.697 nM and 1.53 nM for human and rat endothelin ETA receptors, respectively. In contrast, YM598 exhibits low affinities for human and rat endothelin ET _B receptors, with K _i values of 569 nM and 155 nM,respectively.In measurement of intracellular Ca ²⁺ concentration, Nebentan potassium concentration-dependently inhibits the increase in [Ca ²⁺ ]i induced by 10 nM endothelin-1 in both CHO cells and A10 cells, the IC ₅₀ values are 26.2 nM for CHO cells and 26.7 nM for A10 cells, respectively.

Nebentan potassium (oral administration; 0.1-1 mg/kg; 4 weeks) significantly inhibits the progression of pulmonary hypertension and the development of right ventricular hypertrophy.Nebentan potassium (oral administration; 1 mg/kg; 30 weeks) significantly ameliorates the poor survival rate of CHF rats, it markedly reduces the hypertrophy of both ventricles as well as pulmonary congestion.