title: Thromboxane A2: effects on airway and vascular smooth muscle.
abstract: Thromboxane A2, an unstable compound derived from prostaglandin G2, was generated by incubation of arachidonic acid with a suspension of human platelets. The activity of thromboxane A2 relative to that of prostaglandin H2 in causing contractions of a number of smooth muscle organs were as follows: rabbit aorta, 7-20; human umbilical artery, 9-60; and guinea pig trachea, 2-12. Intravenous injection of thromboxane A2 into anaesthetized quinea pigs was followed by a pronounced increase in the tracheal insufflation pressure, potency compared to prostaglandin H2, 31-45.
mesh_terms: D000818:Animals; D001011:Aorta / Q000187:drug effects; D001808:Blood Vessels / Q000187:drug effects*; D006168:Guinea Pigs; D006801:Humans; D007275:Injections, Intravenous; D009119:Muscle Contraction / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects*; D011817:Rabbits; D013928:Thromboxane A2 / Q000008:administration & dosage / Q000494:pharmacology*; D013931:Thromboxanes / Q000494:pharmacology*; D014132:Trachea / Q000187:drug effects*; D014469:Umbilical Arteries / Q000187:drug effects
chemical_list: D013931:Thromboxanes; D013928:Thromboxane A2