Compounds, compositions, and methods for inhibiting pulmonary hypertension are disclosed. The invention is particularly directed to the use of agents that specifically inhibit the activity of certain endogenously produced epoxyeicosatrienoic acids that promote vasoconstriction of pulmonary arteries. These agents are particularly useful for inhibiting hypoxia-induced pulmonary hypertension. The invention further discloses additional compounds, compositions and methods for increasing pulmonary hypertension.