Protective effects of a prostaglandin oligomer on rats exposed to hypoxia.

To study the protective effects of a prostaglandin E1 oligomer against hypoxia, hypoxia was induced in artificially ventilated rats by replacing the air with 100% nitrogen under anesthesia. Parameters such as survival rate, blood pressure, electrocardiogram, blood lactate, glucose, pH, PO2, PCO2, intracellular adenosine triphosphate, and mitochondrial function were studied. A hypoxia time of 3.5 minutes reduced the survival rate to 50%. However, the prehypoxic administration of 6.0 mg/kg of MR-356, an oligomer synthesized from prostaglandin E1, improved the survival rate to 90%. Similar beneficial effects were also observed when MR-356 was administered either 2 minutes after the start of hypoxia or 30 seconds before the cessation of hypoxia. Systemic parameters were not changed by the administration of the oligomer. The mechanism of action of the oligomer may be to protect membranes during hypoxic insult.