3-Methoxy-4-hydroxyphenylglycol
（重定向自Methoxyhydroxyphenylglycol）
![](/Images/godic/202501/27/3-Methoxy-4-hydroxyphenylglycol.svg5402.png")
![Norepinephrine degradation. 3-Methoxy-4-hydroxyphenylglycol is shown at right. Enzymes are shown in boxes.[2]](/Images/godic/202501/27/Noradrenaline_breakdown.svg5402.png")
3-Methoxy-4-hydroxyphenylglycol (MHPG, MOPEG) is a metabolite of norepinephrine degradation. In the brain, it is the principal norepinephrine metabolite. It is released into the blood and cerebrospinal fluid, and a blood sample of it may therefore be an indication of recent sympathetic nervous system activity.