[Effects of bilaterally injection of AbetaP25-35 to nbM areas on spatial learning in rats].
OBJECTIVE
To investigate the effects of bilaterally injection of amyloid-beta (25-35) peptide (APP25-35) to the nbM areas on the spatial learning and memory in rats.


METHODS
Ten experimental rats were injected bilaterally in the areas of nbM with AbetaP25-35. Another ten rats in the sham-injection group were injected with normal saline. The spatial memory and learning ability of the rats was evaluated by the Morris water maze (MWM) procedure in two, four and six weeks after the injection. The differences between the experimental rats and the sham-injected rats and the changes over time were identified.


RESULTS
The escape latency of the place navigation of the experimental group was significantly longer than the sham-injection group at two weeks after injection (P<0. 01). But such difference disappeared at the later stages (P>0. 05). The experimental rats showed significant longer escape latency at two weeks after injection than at four and six weeks after injection (P<0. 01). The test of the length of time of passing through the platform in the MWM produced similar results. No differences were found between the experimental and sham-injection groups in the escape latency of cue navigation (P>0. 05).


CONCLUSIONS
AbetaP25-35 has transient impacts on the spatial memory and learning behavior in rats. But it does not cause a permanent damage. Short-term exposure to AbetaP will not result in permanent changes of space-learning behavior.
Li
Jin
J
Department of Psychiatry, West China Hospital, Sichuan University, Chengdu 610041, China.
Huang
Ming-sheng
MS
Wang
Xue
X
Kuang
Wei-hong
WH
D016229:Amyloid beta-Peptides / Q000008:administration & dosage* / Q000494:pharmacology*; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D001921:Brain / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology; D004924:Escape Reaction / Q000187:drug effects; D007267:Injections; D007858:Learning / Q000187:drug effects*; D008297:Male; D010446:Peptide Fragments / Q000008:administration & dosage* / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D013028:Space Perception / Q000187:drug effects*
D016229:Amyloid beta-Peptides; D010446:Peptide Fragments; C074636:amyloid beta-protein (25-35)