Delivery of a quaternary pyridinium salt across the blood-brain barrier by its dihydropyridine derivative.

ABSTRACT

A dihydropyridine-pyridine type redox system was successfully applied for delivering a quaternary pyridinium salt, N-methylpyridinium-2-aldoxime chloride (2-PAM), through the blood-brain barrier. The dihydropyridine derivative of 2-PAM was quickly oxidized to 2-PAM after crossing the blood-brain barrier. As a result of this approach, the brain cholinesterase blocked by organophosphates could be reactivated. The new method should be useful in delivering numerous drugs which are otherwise inaccessible to the brain because of their polar ionic character.