This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Adrenergic System, Subject name: Pharmacology
[{'content': 'Wliich of the following is needed for conversion of norepinephrine to epinephrine: \nSelect and explain. \nA. COMT, B. MAO, C. PENMT, D. SAM', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. (c) PENMTRef.:KDT 6th ed. /116* PENMT is Phenylethanolamine N- methyl transferase and is found in the cytosol of only cells of adrenal medullary cells.* PNMT uses S- adenosylmethionine (SAMe) as a cofactor to donate the methyl group to norepinephrine, creating epinephrine.* Epinephrine is synthesized in the medulla of the adrenal gland in an enzymatic pathway that converts the amino acid tyrosine into a series of intermediates and, ultimately, adrenaline.* Tyrosine is first oxidized to L-DOPA, which is subsequently decarboxylated to give dopamine. Oxidation gives norepinephrine.* The final step is methylation of the primary amine of noradrenaline by phenylethanolamine N-methyltransferase (PNMT) in the cytosol of adrenergic neurons and cells of the adrenal medulla (chromaffin cells).', 'role': 'assistant'}]