[Abstract Title]. - Society for Neuroscience

Support: This research was supported by a grant (#R13-2002-005-04001-0) from MRC for Cell
Death Disease Research Center Program funded by the Ministry of Science and Technology of
Republic of Korea.
Title: Involvement of cannabinoid receptors on ethanol induced depression of corticostriatal
synaptic transmission
Authors: *H. CHO 1,3 , K. KIM 1,3 , S. JEUN 1,3 , S. CHOI 1,3 , S. HAHN 2,3 , K.-W. SUNG 1,3 ;
1 Dept. of Pharmacol., 2 Dept. of Physiol., The Catholic Univ. of Korea, Seoul, Republic of Korea;
3 MRC for Death Dis. Center, The Catholic Univ. of Korea, Seoul, Republic of Korea
Abstract: It has been implicated that the dorsal striatum plays a key role in habit formation, and
compulsive alcohol or drug taking and seeking behavior. The dorsal striatum receives
glutamatergic afferent inputs from the cortex and other brain areas, and these glutamatergic
synaptic transmissions may play an important role in behavioral actions related to habit
formation. The purpose of this study was to examine the role of endogenous cannabinoid
systems on ethanol induced depression of synaptic transmission in the rat dorsal striatum.
Acute treatment of ethanol (10 - 150 mM) for 10 minute decreased the corticostriatal excitatory
postsynaptic currents (EPSCs) in a dose-dependent manner. In the presence of AM 251 (5 κM), a
selective cannabinoid 1 (CB1) receptor antagonist, the inhibition of corticostriatal EPSCs by
ethanol was significantly attenuated. However, AM 404 (2 κM), an anandamide transport
inhibitor, had no significant effect on the inhibition of corticostriatal EPSCs by ethanol. These
results suggest that ethanol may not relate with endocannabinoid release, but might act directly
on CB1 receptors. To further clarify our hypothesis, brain slices were pre-treated with WIN
55,212-2 (1 κM), a CB1 receptor agonist, and ethanol did not inhibit corticostriatal EPSCs under
this condition. This data indicates that when CB1 receptors are previously activated by its
agonist, the effect of ethanol on corticostriatal EPSCs is blunted.
Taken together, our results suggest that CB1 receptors are involved in the inhibition of
corticostriatal synaptic transmission by ethanol and might be a direct target for ethanol.
Disclosures: H. Cho, None; K. Kim, None; S. Jeun, None; S. Choi, None; S. Hahn, None; K.
Sung, None.
Poster
274. Basal Ganglia: Transmitters and Neuromodulation II
Time: Sunday, November 16, 2008, 1:00 pm - 5:00 pm
Program#/Poster#: 274.8/JJ3
Topic: D.15.a. Transmitters and neuromodulation