0000000000701374
AUTHOR
Richard A. Houghten
Selected peptides targeted to the NMDA receptor channel protect neurons from excitotoxic death
Excitotoxic neuronal death, associated with neurodegeneration and stroke, is triggered primarily by massive Ca2+ influx arising from overactivation of glutamate receptor channels of the N-methyl-D-aspartate (NMDA) subtype. To search for channel blockers, synthetic combinatorial libraries were assayed for block of agonist-evoked currents by the human NR1-NR2A NMDA receptor subunits expressed in amphibian oocytes. A set of arginine-rich hexapeptides selectively blocked the NMDA receptor channel with IC50 approximately 100 nM, a potency similar to clinically tolerated blockers such as memantine, and only marginally blocked on non-NMDA glutamate receptors. These peptides prevent neuronal cell d…
Activation of bee venom phospholipase A2 through a peptide-enzyme complex
AbstractPhospholipase A2 activation by membrane-bound peptides was investigated in order to understand the role of the membrane-induced conformation on activation, and to examine the occurrence of a peptide-enzyme complex at the lipid/water interface. For the peptides studies, bee venom phospholipase A2 was stimulated regardless of the membrane-bound conformation (α-helix, β-sheet or random coil). Using antisera raised against melittin, we were able to demonstrate the occurrence of a calcium-dependent complex involving the enzyme, phospholipid substrate, and peptide.