9,11-methane-epoxy PGF1α is a stable epoxymethano analog of PGH1 that produces a strong and dose-related aggregation of washed rabbit platelets (EC50 = 0.88 μM) and contraction of rabbit aortic strips (EC50 = 0.11 μM).{14125} 9,11-methane-epoxy PGF1α induces contraction of guinea pig tracheas (EC50 = 3.4 μM) with a maximal contraction of about 60% of that caused by a submaximal dose of histamine.