[Abstract Title]. - Society for Neuroscience

Disclosures: T. Ho, None; K.A. Pelkey, None; C.J. McBain, None.
Poster
238. LTD: Hippocampus and Cortex
Time: Sunday, November 16, 2008, 1:00 pm - 5:00 pm
Program#/Poster#: 238.3/D48
Topic: B.08.f. Long-term depression ( LTD )
Support: CIHR
Title: The effects of ethanol on long-term depression in both the CA1 and dentate gyrus
Authors: *J. D. SHIN 1 , R. PETERSEN 1 , B. R. CHRISTIE 2 ;
1 Biol., 2 Div. of Med. Sci., Univ. Victoria, Victoria, BC, Canada
Abstract: Alcohol is a widely consumed drug that has a multitude of effects on the brain and
body. Numerous studies have shown that direct application of ethanol can block long-term
potentiation, a biological model of learning and memory, less is known of its effects on longterm
depression (LTD). Some studies have shown ethanol to enhance LTD (Hendricson et al.,
2002), while others have found ethanol blocks LTD (Izumi et al., 2005) in the CA1 region. Field
excitatory post synaptic potentials (fEPSPs) were recorded from rat (p14-p28) hippocampal
slices (400 micron). Hippocampal slices were recorded in normal aCSF at 30 degrees Celsius.
After obtaining a stable baseline, a low frequency stimulus protocol (900 pulses at 1Hz) was
applied in either the presence or absence of ethanol containing ACSF (50 or 100mM). In the
CA1 region, 100mM ethanol had a greater inhibition on LTD than 50mM ethanol. In contrast,
LTD was more severely attenuated by 50mM ethanol than 100mM in dentate gyrus (DG)
recordings. In conclusion, our results indicate that ethanol reduces LTD in both the CA1 and DG
subfields of the hippocampus. In the CA1 an increase in ethanol concentration led to an increase
in LTD inhibition. However, in the DG, with a decrease in inhibition was observed with
increasing ethanol concentration, suggesting that the effects of ethanol are at multiple receptor
subtypes.
Disclosures: J.D. Shin , None; R. Petersen, None; B.R. Christie, None.
Poster