3, 4 dihydroxyphenylethyleneglycol (DHPG) formation: The major route of rat brain norepinephrine metabolism

Abstract

• 1.

  1. The regional formation rates of conjugated DHPG and MHPG in rat brain were estimated by determining their rates of accumulation following probenecid administration.

• 2.

  2. Brain regional conjugated DHPG formation rates correlated significantly with the regional steady state levels. This did not apply in the case of conjugated MHPG.

• 3.

  3. The formation rates of conjugated DHPG significantly exceeded those of conjugated MHPG in hypothalamus, midbrain, brainstem, hippocampus and cerebral cortex.

• 4.

  4. These findings clearly indicate that conjugated DHPG formation is the major route of rat brain NE metabolism and also suggests DHPG levels are more indicative of rat brain NE turnover, under resting conditions.