Y. Satoh et al., beta-amyloid peptides inhibit acetylcholine release from cholinergic presynaptic nerve endings isolated from an electric ray, NEUROSCI L, 302(2-3), 2001, pp. 97-100
We investigated the effects of beta -amyloid (A beta) peptides on cholinerg
ic synaptosomes isolated from the electric organ of the Japanese marine ray
Narke japonica. Fresh and pre-incubated solutions of A beta (1-42) inhibit
ed acetylcholine (ACh) release from the synaptosomes evoked by high [Kt] de
polarization when incubated with synaptosomes for 10 min before the depolar
izing stimulus. A freshly prepared solution of A beta (1-40) did not inhibi
t the evoked ACh release, but prolonged pre-incubation of A beta (1-40) sol
ution caused the inhibition. A beta (1-15) neither in fresh nor pre-incubat
ed solution inhibited. These results have demonstrated that A beta peptides
can acutely inhibit the depolarization-evoked release of ACh by acting dir
ectly on cholinergic presynaptic nerve endings. The electrophoresis analysi
s showed a strong correlation between A beta aggregation and its inhibition
for ACh release. (C) 2001 Elsevier Science Ireland Ltd. All rights reserve
d.