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Operant Self‐Administration of Ethanol in Sardinian Alcohol‐Preferring Rats
Author(s) -
Vacca Giovanni,
Serra Salvatore,
Brunetti Giuliana,
Carai Mauro A. M.,
Samson Herman H.,
Gessa Gian Luigi,
Colombo Giancarlo
Publication year - 2002
Publication title -
alcoholism: clinical and experimental research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.267
H-Index - 153
eISSN - 1530-0277
pISSN - 0145-6008
DOI - 10.1111/j.1530-0277.2002.tb02470.x
Subject(s) - ethanol , self administration , alcohol , extinction (optical mineralogy) , reinforcement , sucrose , chemistry , zoology , endocrinology , medicine , psychology , biochemistry , biology , social psychology , mineralogy
Background “Work” for ethanol, that is, the ability of a laboratory animal to press a lever to gain access to ethanol, has been proposed as (a) a requirement for definition of an animal model of alcoholism and (b) a measure of ethanol‐reinforcing properties. The present study evaluated oral self‐administration of ethanol under an operant (lever pressing) procedure in selectively bred Sardinian alcohol‐preferring (sP) and alcohol‐nonpreferring (sNP) rats. Methods Rats from both lines were initiated to self‐administer 10% ethanol, on a fixed ratio 1 schedule and in daily 30 min sessions, by using the Samson sucrose fading procedure. Subsequently, rats were exposed to increasing concentrations of ethanol up to 30% on a fixed ratio 4 schedule. Finally, the extinction responding for ethanol, defined as the maximal number of lever responses reached by each rat in the absence of ethanol reinforcement, was determined. Results The results indicated that sP rats acquired and maintained lever pressing for ethanol, self‐administering mean amounts of ethanol in the range of 0.6 to 1.1 g/kg/session, which gave rise to mean blood ethanol levels in the 30 to 45 mg% range. Extinction responding for ethanol in sP rats averaged 73. In contrast, once sucrose was faded out, sNP rats displayed minimal levels of responding for ethanol, and extinction responding averaged 6. Conclusions The results of the present study extend to the sP/sNP rat lines the finding that ethanol can be established as a reinforcer in selectively bred alcohol‐preferring rats, whereas it has modest, if any, reinforcing properties in alcohol‐nonpreferring rats.