Spasmogenic qualities of prostaglandin F2alpha in the cat

Available data indicate that the concentration of prostaglandin F2alpha required to produce arterial spasm in an experimental model is approximately a thousand-fold higher than the concentration that occurs under physiological conditions. The spasmogenic platelet factor which has been previously described is shown to be a substance other than prostaglandin F2alpha because of differences in susceptibility of the two substances to enzymatic digestion.