6-ketoprostaglandin-f1-alpha and Hypotension--Orthostatic

We measured urinary excretion of the principal metabolite of prostacyclin, PGI-M (2,3-dinor-6-keto-PGF1 alpha) in two patients with Shy-Drager syndrome and three with idiopathic orthostatic hypotension. All patients had a rise in blood pressure (30 +/- 6 mm Hg) after ingestion of 50 mg indomethacin. Urinary excretion of PGI-M was normal and fell 57 +/- 11% after administration of indomethacin. In two subjects, there was no evidence of any circulating inhibitor of platelet aggregation when hypotension was induced by upright posture or ingestion of a meal. Despite the efficacy of indomethacin, these patients with autonomic dysfunction did not show increased production of the vasodilator prostanoid prostacyclin.

Topics: 6-Ketoprostaglandin F1 alpha; Aged; Autonomic Nervous System Diseases; Female; Humans; Hypotension, Orthostatic; Indomethacin; Male; Middle Aged; Platelet Aggregation; Shy-Drager Syndrome