Does context influence the duration of locomotor sensitization to ethanol in female DBA/2J mice?

Abstract

Rationale-Repeated exposure to many abused drugs produces a progressive increase in locomotor sensitivity, referred to as locomotor sensitization. Locomotor sensitization may persist for some time following termination of repeated drug administration, and contextual learning appears to facilitate expression of the behavioral phenomenon. However, relatively little is known about the persistence of and the degree to which contextual learning influences locomotor sensitization to alcohol (ethanol).Objectives-The goal of the present work was determine the duration of locomotor sensitization to ethanol and the degree to which contextual learning positively influences the induction, expression, and persistence of the behavioral phenomenon in DBA/2J mice.Methods-Sensitized (with or without ethanol-paired exposure to the testing chamber)and nonsensitized saline control mice were left undisturbed in their home cages until subsequent ethanol challenge and testing in the locomotor activity testing chambers 7, 14, 21, 28, 42, 56, and/or 70 days after cessation of the ethanol sensitization procedure. Retro-orbital sinus bloods were sampled to determine whether the sensitization procedure had altered blood ethanol clearance rates.Results-Locomotor sensitization persisted through post-sensitization day 14, and contextual learning prolonged the expression of this phenomenon through at least post-sensitization day 28. Blood ethanol concentrations did not differ in any experiment.Conclusions-Locomotor sensitization to ethanol persists for some time after cessation of repeated ethanol exposure and the association of contextual cues with the ethanol experience lengthens this persistence. The present data lay the groundwork for investigations into the neuroadaptive changes that underlie locomotor sensitization to ethanol in mice.

Parametric analysis of the development and expression of ethanol-induced behavioral sensitization in female Swiss mice: effects of dose, injection schedule, and test context

“…This conclusion is supported by the results of the test session, both when ethanol sensitization is recorded on the whole 30-min test session and when only the first 5 min of the test session are considered. These results are in agreement with those of Boehm et al (2008) who found no significant differences in the first sensitization test between DBA/2J mice sensitized within or outside the test context. The present results also agree with those of several other authors who routinely use sensitization procedures in which ethanol is injected in the colony room (e.g., Meyer and Phillips 2007;Quadros et al 2002).…”

“…Such an experimental protocol has been used to demonstrate the context dependency of the behavioral sensitization to many drugs, including cocaine, amphetamines, dopamine agonists, and nicotine (Crombag et al 2000;Hooks et al 1993;Reid et al 1996;Szumlinski et al 1997). In contrast to these drugs, few experimental studies have yielded clear and unambiguous results on the context dependency of ethanol sensitization (Boehm et al 2008;Cunningham and Noble 1992;Meyer et al 2005;Quadros et al 2003). To examine if ethanol acts like psychostimulants to induce context-dependent sensitizing effects, we compared the effects of ethanol injected in a specific test or home cage environment.…”

Ethanol-induced locomotor sensitization in DBA/2J mice is associated with alterations in GABAA subunit gene expression and behavioral sensitivity to GABAA acting drugs

“…On days 4-13 mice assigned to the RE group received a 2.5 g/kg ethanol dose once daily and mice in the RS group continued to receive an equivalent volume of saline each day. This 0.5 g/kg higher dose was chosen based on literature demonstrating its effectiveness at inducing strong locomotor sensitization in mice using similar paradigms (Lessov & Phillips, 1998; Meyer et al , 2005), including data from our lab (Boehm et al, 2008). None of the mice were tested in the locomotor activity testing chambers following injection on days 4-13; mice were placed immediately into their home cage following injection.…”

Blockade of Ethanol-Induced Behavioral Sensitization by Sodium Butyrate: Descriptive Analysis of Gene Regulations in the Striatum

“…We used female DBA/2J mice as described in other studies (Boehm et al, 2008;Botia et al, 2012;Didone et al, 2008). Mice were purchased from Janvier (Le Genest Saint Isle, France) and were housed 10 per cage and acclimated to the colony room for at least 10 days.…”