This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Hypeension, Arrhythmias, Dyslipidemia, Subject name: Pharmacology
Which antihypeensive is a prodrug and is conveed to its active form in brain? 
Select and explain. 
A. Clonidine, B. Methyl dopa, C. Minoxidil, D. Nitroprusside
B: Methyl dopa
Answer: B: Methyl dopa 
Explanation: Both methyldopa and minoxidil are prodrugs. Conversion of methyl dopa to a-methylnorepinephrine takes palce in the brain. Minoxidil is activated to minoxidil sulphate (by phase II reaction) in the periphery.