Blood brain barrier: the role of pyridoxine.

The central nervous system (CNS) is a closed system guarded by the blood brain barrier (BBB), with a complicated network of microvascular endothelial cells, astrocytes, and neurons engaged in selective neurophysiological mechanisms. Exploration for a molecule such as a cofactor, hormone, enzyme, signaling molecule, or second messenger (collectively addressed as CHESS as we proceed), which has the ability to cross the BBB will be the goal of this hypothesis. The ratio of amino acids (AA) to neurotransmitters (NT) is over one-to-one thousand in the CNS, with the ultimate effect at the end receptor level. Diagnostic modalities utilizing oxygen and glucose for identifying organic brain diseases via functional properties have become popular. Delineation from the background signal, however, poses an enormous challenge. Targeting neurotransmitter metabolism with little or possibly no background signal using a cofactor able to cross the BBB is hypothesized.