Objective To inveatigate the effect of 15-HETE, a metabolite of arachidonic acid, on isolated hypoxic pulmonary arterial ringa ( PARs) , trying to find appropriate treatment for pulmonary hypertension and its complications during anesthesia in order to avoid hypoxemia. Methods Sixteen healthy Wistar rats of either sex weighing (230 ± 10) g were randomly divided into two groups : A control group breathing fresh air (FiO2 =21%) and B hypoxia group breathing hypoxic air (N2 = 90% , O2 = 10% ) in a hypoxic box....