[Effect of tyramine on the cerebrovascular resistance and arterial pressure during the action of prostaglandins E].

A resistographic study of the cerebrovascular resistance (CVR) and of the arterial blood pressure showed prostaglandins (PG), type E, to inhibit the pressor action of tyramine on the cerebral vessels and the blood pressure. Indomethacin--an inhibitor of PG biosynthesis, retarded the tyramine tachyphylaxis and restored its pressor effect. Ipraside, the monoaminooxidase inhibitor, failed to influence the speed of tyramine tachyphylaxis development under conditions of indomethacin infusion, but increased the pressor effect of tyramine. It is supposed that inomethacin influence was based on the hypersensitivity of the vascular adrenoreceptors.