EFFECTS OF 9-AMINO-1,2,3,4-TETRAHYDROACRIDINE (THA) ON ATP-DIPHOSPHOHYDROLASE (EC-3.6.1.5) AND 5'-NUCLEOTIDASE (EC-3.1.3.5) FROM RAT-BRAIN SYNAPTOSOMES

1. 9-Amino-1,2,3,4-tetrahydroacridine (THA), an acetylcholinesterase i nhibitor, significantly inhibited in vitro the ATP diphosphohydrolase activity of synaptosomes from the cerebral cortex and hippocampus of a dult rats. 2. THA did not inhibit in vitro the 5'-nucleotidase activit y of synaptosomes from cerebral cortex and hippocampus of rats. 3. THA exerted an uncompetitive inhibition on ATP diphosphohydrolase activit y. This mechanism of inhibition was the same in the 2 different synapt osomal fractions (cerebral cortex and hippocampus) studied. 4. THA, pr oposed as a drug for the treatment of Alzheimer's disease, can alter i n vitro ATP degradation in synaptosomes from the central nervous syste m. (C) 1997 Elsevier Science Inc.