Enhancement of NMDA responses by beta-amyloid peptides in the hippocampus in vivo.
The effects of Alzheimer's disease-related beta-amyloid (Abeta) peptides on the N-methyl-D-aspartate (NMDA)-evoked cell firing rate were studied in hippocampal CA1 neurons of the rat. Extracellular single-unit recordings were combined with iontophoretic applications that allowed quantitative analyses of the interactions between Abeta peptides and NMDA receptor-mediated events in vivo. The NMDA responses were significantly increased both by the full length Abeta1-42 and by its model fragment Abeta25-35. Enhancements of the NMDA responses by the Abeta peptides lasted about 15 min and were irreversible. The effects of Abeta25-35 were prevented by the pentapeptide Lys-Leu-Val-Gly-Phe-amide (KLVGF) and were not evoked when its reversed sequence (Abeta35-25) was applied.
Molnár
Zsolt
Z
Department of Medical Chemistry; Department of Biology, Juhász Gyula College, University of Szeged, Boldogasszony sgt. 6, Szeged 6721, Hungary.
Soós
Katalin
K
Lengyel
Imre
I
Penke
Botond
B
Szegedi
Viktor
V
Budai
Dénes
D
D000200:Action Potentials / Q000187:drug effects; D016229:Amyloid beta-Peptides / Q000494:pharmacology*; D000704:Analysis of Variance; D000818:Animals; D004357:Drug Synergism; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology*; D006624:Hippocampus / Q000187:drug effects*; D007478:Iontophoresis / Q000379:methods; D008297:Male; D016202:N-Methylaspartate / Q000494:pharmacology*; D010455:Peptides / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors
D016229:Amyloid beta-Peptides; D018690:Excitatory Amino Acid Agonists; D010455:Peptides; D016202:N-Methylaspartate