Barrier mechanisms for neurotransmitter monoamines and their precursors at the blood‐brain interface

  title={Barrier mechanisms for neurotransmitter monoamines and their precursors at the blood‐brain interface},
  author={Jan Erik Hardebo and Ch. Owman},
  journal={Annals of Neurology},
The integrity of the endothelial cell lining of the cerebrovascular bed constitutes a morphological blood‐brain barrier mechanism to neurotransmitter monoamines. Circulating monoamines are prevented from entering the brain primarily at the luminal membrane of the endothelial lining. The small percentage of amines that may pass this membrane is deaminated within the endothelial cells and pericytes of brain microvessels (capillaries, venules, and small veins) and, in the case of large parenchymal… 

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The brain develops and functions within a strictly controlled environment resulting from the coordinated action of different cellular interfaces located between the blood and the extracellular fluids

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The endothelial cells and pericytes of brain microvessels (capillaries and small veins) are equipped with an enzymatic barrier, impeding the passage of circulating amino acids into the brain, showing considerable species variation.


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