Different pattern of brain c-Fos expression following re-exposure to ethanol or sucrose self-administration environment.
Exposure of alcohol addicts to alcohol-related environmental cues may elicit alcohol-seeking behavior and lead to relapse to heavy drinking. The aim of the present study was to identify brain regions activated by alcohol (ethanol)-related stimuli in Wistar rats trained to lever press for 8% ethanol solution in operant self-administration cages. Ethanol self-administration was stabilized in a maintenance phase, which lasted for 30 days. c-Fos protein expression was used as a marker of neuronal activation.Re-exposure to ethanol self-administration environment after 30-day but not after 24-h abstinence increased the number of Fos-positive nuclei in the thalamic paraventricular nucleus, granular insular cortex and medial prefrontal cortex. In general, no differences were found in c-Fos protein expression between the rats allowed to self-administer alcohol and the subjects exposed only to alcohol-related stimuli. In contrast, no increase in c-Fos immunoreactivity was observed in rats trained to lever press for sucrose solution and exposed to sucrose-related environmental stimuli after 30-day abstinence. Taken together, these results suggest that at least some thalamo-cortical circuits become more responsive to ethanol-paired stimuli after prolonged abstinence and that ethanol- and sucrose-seeking behavior may be regulated by partially different neural mechanism(s).
Department of Pharmacology, Institute of Pharmacology, Polish Academy of Sciences, Smetna 12 Street, 31343, Krakow, Poland.
Krzysztof
K
Wedzony
Eliza
E
Koros
Anna
A
Czyrak
Agnieszka
A
Chocyk
Klaudia
K
Czepiel
Katarzyna
K
Fijal
Marzena
M
Mackowiak
Artur
A
Rogowski
Wojciech
W
Kostowski
Przemyslaw
P
Bienkowski
D000818:Animals; D001835:Body Weight / Q000187:drug effects; D001921:Brain / Q000378:metabolism*; D003216:Conditioning, Operant / Q000187:drug effects; D000431:Ethanol / Q000008:administration & dosage / Q000494:pharmacology*; D005108:Extinction, Psychological; D015870:Gene Expression; D007150:Immunohistochemistry; D008297:Male; D009928:Organ Specificity; D016760:Proto-Oncogene Proteins c-fos / Q000096:biosynthesis* / Q000235:genetics; D051381:Rats; D012646:Self Administration; D013395:Sucrose / Q000008:administration & dosage / Q000494:pharmacology*
D016760:Proto-Oncogene Proteins c-fos; D000431:Ethanol; D013395:Sucrose