2-AMINO-3-(METHYLAMINO)PROPANOIC ACID (BMAA) BIOAVAILABILITY IN THE PRIMATE

2-Amino-3-(methylamino)-propanoic acid (BMAA) is a low potency excitat ory amino acid present in the cycad plant that has been proposed as a factor in the high incidence of amyotrophic lateral sclerosis-parkinso nism dementia (ALS-PD) in the western Pacific region. We employed stab le isotopic forms of BMAA to assess the oral bioavailability of this c ompound in cynomologus monkeys (n = 3). The stable isotope labeled BMA A ([N-15]-BMAA) was injected i.v. at the same time that the unlabeled compound was administered orally. Both forms of BMAA were then quantif ied in a 48h urine sample by gas chromatography-mass spectrometry (GC/ MS). Following oral dosing, 80% of the administered BMAA was absorbed into the systemic circulation; thus, oral bioavailability was high and other routes of administration could not result in significantly high er circulating levels of BMAA for a given administered dose.