Norepinephrine and epinephrine Metabolism MAO B2b28-=b MHPG(3甲氧4羟苯乙二醇 CH2-NH2 -CH2 was used as an index of cns ne turnover Norepinephrine DOPGAL Epinephrine but generated mostly from aldehyde COMT aldehyde reducts COMT periphery CH,O VMA(香草扁桃酸) sometimes used as an index of ne turnover Normetanephrine DOPEG DOMA Metanephrine Sulfate conjugates COMT COM also prevalent Elimination by kidneys MOPEG or MHPG VMA VMA Urine MHPG-SO NMN-SO reductase dehydrogenase MN-SO MAO Relative amounts excreted MOPGALNorepinephrine and Epinephrine Metabolism MHPG (3-甲氧4-羟苯乙二醇): was used as an index of CNS NE turnover but generated mostly from periphery VMA(香草扁桃酸): sometimes used as an index of NE turnover Sulfate conjugates also prevalent or MHPG 6