This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous (Pharmacology), Subject name: Pharmacology
Selegiline is 
Select and explain. 
A. Dopa decarboxylase inhibitor, B. MAO-B inhibitor, C. COMT inhibitor, D. MAO-A inhibitor
B: MAO-B inhibitor
Answer: B: MAO-B inhibitor 
Explanation: (B) MAO-B inhibitor # Selegiline is a MAO-B inhibitor.> MAO exist in forms MAO-A & MAO-B.> MAO-A predominates in peripheral adrenergic structures & intestinal mucosa.> MAO-B predominates in brain & Blood platelets. Selegline, along c- levodopa, prolongs its action, & wearing-off effect.> Based on the theory that oxidation of DA or toxin MPTP in the striatum by MAO to free radicals is cause for parkinsonism early therapy c- selegiline night delay progression of disorders.> Non selective MAO inhibitors include: Phenelzinec/lsocarboxazide/Tranylcypromine.> Selective MAO-A are: Clorgiline/ Moclobemidee> Selective MAO-B are: Selegiline (Deprenyl), Rasagline, Periphery, BLood brain barrier