Changes in rat hypothalamic and brain stem catecholamine concentrations following acute administration of phenylethanolamine-N-methyltransferase inhibitors.
The effect of acute phenylethanolamine-N-methyltransferase (PNMT) inhibition on rat brain catecholamine concentrations was studied. All PNMT inhibitors tested were effective in depleting hypothalamic and brain stem epinephrine. Norepinephrine concentrations were unaffected; however, dopamine levels were increased in all areas studied. While several possible explanations are offered for this phenomenon, the mechanism is not yet understood.