Ethanol preference in the Harrington derivation of the Maudsley Reactive and Non-Reactive strains.
ABSTRACT Ethanol intake was explored in the Harrington derivation of the Maudsley Reactive and Maudsley Non-Reactive rat strains (MR/Har and MNRA/Har). When 5% and 10% ethanol solutions were presented as the sole source of fluid (1-bottle test), MR/Har rats, respectively, ingested 15% more, or 9% less, than their baseline water intake, whereas MNRAs ingested 6% less, or 42% less than their baseline intake. However, because MNRA/Har rats drank significantly more water than MR/Har's under ad libitum conditions (MNRA/Har, 46.6 +/- 1.83 ml; MR/Har 32.45 +/- 1.64 ml/24 hr), males and females of the two strains ingested a similar amount of ethanol in the 1-bottle test (5% ethanol, 4-7; 10% ethanol, 6-12 g/kg body weight/24 hr). In 2-bottle free-choice tests administered after an extended period of forced ethanol consumption, MR/Har male and female rats exhibited a strong ethanol preference (X = 80%) and consumed a larger amount of ethanol (MR/Har, 7-13; MNRA/Har, 6-9 g/kg body weight/24 hr) than MNRA/Har's. Across all conditions, females of both strains ingested a greater relative amount of ethanol than males. The strain difference in ethanol preference was found to be independent of prior exposure to ethanol because it was also found when 2-bottle free-choice tests were carried out in naive animals (Experiment 2). The pattern of development of ethanol preference in individual animals was characterized by abrupt onset, after variable periods of exposure to the 2-bottle choice test, and maintenance of strong ethanol preference thereafter. The extensive behavioral and biological definition of the Maudsley strains is a valuable asset in attempting to elucidate the biobehavioral correlates of ethanol preference.
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ABSTRACT: Saccharin and ethanol intakes were measured in seven strains of rats known to differ in their preferences for ethanol: The Fawn-Hooded (FH), alcohol-preferring (P) and Maudsley Reactive rats have been reported to drink ethanol voluntarily, whereas the alcohol-nonpreferring, Maudsley Nonreactive and Flinders Line (FSL and FRL) rats do not. Saccharin and ethanol intakes were highly correlated (r =+0.61) over all strains, with the FH rats drinking the most of both solutions. Correlation coefficients between pairs of drinking versus nondrinking rat strains were even higher. In a second experiment, genetically heterogeneous F2 progeny from cross-breeding the ethanol-preferring FH rats with the ethanol-nonpreferring Flinders Resistant Line (FRL) rats were studied. The results indicated a high positive correlation between saccharin and ethanol intakes (+0.65). These findings suggest that the association between saccharin and ethanol intakes previously reported in rat strains with different preferences for ethanol may have a similar genetic basis.Alcoholism Clinical and Experimental Research 03/1993; 17(2):366 - 369. · 3.31 Impact Factor
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ABSTRACT: Young male and female Sprague-Dawley rats (30 days old) were assigned randomly to three treatment groups: (1) alcohol treatment—received beer with 5% ethanol added, food, and water ad libitum; (2) pair-fed treatment—received nonalcoholic beer plus sucrose and food to match intake by the alcohol-treated animals; and (3) control treatment—received food and water ad libitum. Animals were tested for alcohol preference for 24 hr and then received their assigned treatments for a period of 30 days, followed by a period of abstinence before alcohol preference testing again at 74 days of age. Males given free access to beer and water did not drink large quantities of beer. Females given free access to beer and water drank a lot of beer on the first day, but decreased intake until ˜52 days of age. A developmental change in young female rats at ˜52 days of age resulted in increased voluntary ethanol intake, possibly caused by hormonal changes associated with the establishment of estrous cycles. When the animals were tested for alcohol preference at 74 days of age after a period of abstinence, males and females in the pair-fed group had greater alcohol preference than animals in the other groups. Females in the pair-fed group had greater alcohol intake based on body weight than males in the pair-fed group and males and females in all other groups. These results provide insight into sex differences in the development of voluntary drinking behavior and responses of drinking behavior to the early stress of pair-feeding.Alcoholism Clinical and Experimental Research 04/2006; 20(6):1043 - 1049. · 3.31 Impact Factor
- Alcoholism-clinical and Experimental Research - ALCOHOL CLIN EXP RES. 01/2001; 25(3):391-402.