DBH is a 290 kDa copper-containing oxygenase. It can be detected in noradrenergic nerve terminals of the central and peripheral nervous systems, and is also expressed in chromaffin cells of the adrenal medulla. DBH contains our identical subunits, and its activity requires ascorbate as a cofactor. It functions in in the synthesis of small-molecule neurotransmitters that is membrane-bound, making norepinephrine the only transmitter synthesized inside vesicles. DBH has been shown to be associated with decision making and addictive behaviors such as alcohol and smoking, attention deficit hyperactivity disorder, and also with neurological diseases such as Schizophrenia and Alzheimer's.