Which of the following agents used in hypeension is a prodrug that is conveed to its active form in the brain?: (A) Doxazosin, (B) Methyldopa, (C) Clonidine, (D) Nitroprusside
Answer is B. Methyldopa (L-a-methyl-3,4-dihydroxyphenylalanine) is an analog of L-dopa. Methyldopa enters the brain an aromatic amino acid transpoer and is conveed to a-methyldopamine and a-methylnorepinephrine. Antihypeensive action appears to be due to stimulation of central a adrenoceptors by a-methylnorepinephrine or a-methyldopamine.Katzung Pharmacology 12th edition Pg: 175