Synthesis of this compound is rate-limited by an enzyme that the W317X (“w-three-seventeen-x”) mutation truncates in Tourette’s syndrome. This is the main substrate of a copper-dependent enzyme that also metabolizes putrescine and cadaverine. Patients with intolerance for this compound take diamine oxidase supplements (15[1])to break down this compound and avoid scombroid poisoning. (-5[1])The first blockbuster drug, cimetidine, selectively inhibits parietal cells’ receptors for this compound (15[1])to treat (*) stomach ulcers. This compound is made by decarboxylating an imidazole-containing amino acid. The OTC drugs loratadine and cetirizine (10[1])block this compound’s activity after IgE causes its release from mast cells, (10[1])preventing a runny nose and itching. For 10 points, seasonal allergies are treated by drugs that target what inflammatory compound? (10[1])■END■