Alcohol Self-administration in Two Rat Lines Selectively Bred for Extremes in Anxiety-related Behavior

Abstract

According to the tension reduction hypothesis, individualsThe anxiolytic effect of alcohol may be one important motivation for its consumption, at least in individuals who are susceptible to this effect (Pohorecky 1981;Spanagel et al. 1995). It has been argued in the so-called "tension reduction hypothesis" by Conger (1956), that in situations where alcohol consumption is fear-reducing, this effect reinforces alcohol consumption and may, therefore, promote future alcohol intake. This hypothesis predicts that more anxious individuals should benefit more from the anxiolytic effect of alcohol and therefore consume more alcohol than less anxious individuals.The validity of this concept is still a matter of debate, because its direct assessment is difficult, and only a few

Comparison of voluntary ethanol intake by two pairs of rat lines used as genetic models of anxiety

“…As mentioned before, these findings are in agreement with the study by Henniger et al (13), which also used rat lines selectively bred for differences in anxiety responses, although there are some methodological differences between the two studies: in our study the rats had a choice between water and low concentrations of ethanol solutions (2 and 4%, respectively) in a 2-bottle paradigm, while in the study of Henniger et al (13), rats had a choice between water and higher ethanol concentrations (5, 10 and 20%, respectively) in a 4-bottle paradigm from the beginning to the end. Although we did not measure blood ethanol levels, it should be pointed out that rats usually prefer alcohol solutions of lower rather than higher concentrations (i.e., >6% (v/v) ethanol solutions), probably due to taste aversion.…”

“…These data support and extend the interpretation put forward by Henniger et al (13), that these factors might not necessarily be co-selected when animals are selectively bred either for differences in emotionality or for differences in ethanol preference. In this context, it is important to mention that findings from the National Comorbidity Survey (32) did not demonstrate a significant correlation between anxiety disorders and alcohol use disorders.…”

“…In addition, confirming other studies, female rats displayed a higher ethanol drinking pattern than male rats (18-21) regardless of strain. Although at variance with the study of Spanagel et al (3), which reported that "anxious" rats consumed significantly more ethanol than "non-anxious" rats selected on the elevated plus-maze test, the present results confirm and extend recent findings suggesting that increased levels of inborn anxiety and high alcohol consumption are not necessarily related (12,13).…”

“…Recently, a study by Fernández-Teruel et al (12) indicated that apparently there is no direct relationship between trait anxiety, which is higher in Roman low-avoidance rats compared to Roman high-avoidance rats, and alcohol consumption. In addition, Henniger et al (13), using rats bred and selected for differences in anxiety-related behavior on the elevated plus maze, also showed no relationship between anxiety and ethanol consumption.…”

Conceptual framework for the etiology of alcoholism: a ?kindling?/stress hypothesis

“…However, this concept continues to be a matter of debate as stressors have had mixed effects on alcohol drinking in preclinical studies (Pohorecky 1990;Chester et al 2004;Breese et al 2004a). With regard to anxiety as a reflection of "tension," Henniger et al (2002) were unable to relate alcohol ingestion to anxiety in rats selectively bred for anxiety-like behavior.…”