Author/Authors :
Alijan-pour، Jafar نويسنده School of Biology, Damghan University, Damghan, Iran , , Abrari، Kataneh نويسنده School of Biology, Damghan University, Damghan, Iran , , Lashkar bluki، Taghi نويسنده School of Biology, Damghan University, Damghan, Iran , , Ghorbanian، Mohammad Taghi نويسنده Department of Biology, Damghan University, Damghan, Iran , , Goudarzi، Iran نويسنده School of Biology, Damghan University, Damghan, Iran , , Elahdadi Salmani، Mahmoud نويسنده School of Biology, Damghan University, Damghan, Iran ,
Abstract :
Objective: This research study is an attempt to examine whether the administration of
ethanol after memory reactivation would modulate subsequent expression of memory in
rats. Additionally, we examined whether this administration alters the density of Cornu Ammonis
(CA)1 and CA3 pyramidal and dentate gyrus (DG) granule cells.
Materials and Methods: In this experimental study, adult male Wistar rats (200-300 g)
were trained in a fear conditioning system using two 1 second, 0.6 mA shocks with an
interval of 180 seconds. Twenty four hours later rats were returned to the chamber for 120
seconds. Immediately after reactivation they were injected with ethanol (0.5, 1, 1.5 mg/
kg) or saline. 1, 7 and 14 days after reactivation, rats were returned to the context for 5
minutes. Seconds of freezing (absence of all movement except respiration) were scored.
In the second experiment (described in the previous paragraph), after test 1, animals
were anesthetized with sodium pentobarbital and perfused transcardially with phosphate
buffer (10 minutes) and 4% paraformaldehyde (15 minutes). The brains were postfixed in
phosphate-buffered 4% paraformaldehyde (24 hours) and 30% sucrose. 10-?m sections
were stained with cresyl violet.
Data were analyzed by 1-and 2-way ANOVA for repeated measurements by means of
SPSS 16.0. Tukey’s post hoc test was performed to determine the source of detected
significant differences. P < 0 .05 were considered significant. Data are presented as mean
± SEM.
Results: Findings from the first experiment indicated that ethanol at a dose of 1.5 mg/kg
significantly impaired recall of memory only in the first test. The density of CA1 and CA3
pyramidal and DG granule cells in the ethanol group was decreased (p < 0.01) compared
with control group respectively 43.7%, 35.8%, and 37.8.
Conclusion: The data demonstrate that ethanol exposure impairs post retrieval processes.
Moreover, ethanol decreases the density of CA1, CA3 and DG cells. Presumably it
would be a correlation between our behavioral and histological results.
