The effect of aluminium chloride upon the transition of drugs through the blood-brain barrier into the central nervous system.

In order to determine the effect of Al3+ upon the transition of drugs through the blood-brain barrier into the central nervous system we examined its effect upon a drug that dissociates as a cation (quinidine) and drugs that dissociate as anions (acetylsalicylic acid and pentobarbital). The entry and exit of quinidine into and out of the brain in mice pre-treated with AlCl3 was inhibited. Al3+ did not compete with acetylsalicylic acid for the penetration through the blood-brain barrier but did slow down its elimination from the brain. Brain kinetics of the examined drugs showed good correlation with their central pharmacodynamic effects.