Ambient Temperature Effects on Taste Aversion Conditioned by Ethanol: Contribution of Ethanol‐Induced Hypothermia

Abstract

Six experiments examined the effects of low (5-10 degrees C), normal (21 degrees C), or high (32 degrees) ambient temperature on conditioned taste aversion and body temperature changes produced by ethanol, lithium chloride, or morphine sulfate. Fluid-deprived rats received five to seven taste conditioning trials at 48-hr intervals. On each trial, access to saccharin at normal ambient temperature was followed by injection of drug or saline and placement for 6 hr into a temperature-controlled enclosure. Exposure to low ambient temperature facilitated, whereas exposure to high ambient temperature retarded acquisition of ethanol-induced conditioned taste aversion. The ability of an alteration in ambient temperature to influence conditioned taste aversion varied as a function of ethanol dose and was related to ambient temperature's effect on ethanol-induced hypothermia. More specifically, strength of conditioned taste aversion was negatively correlated with core body temperature after ethanol injection. Alterations in ambient temperature alone did not affect ingestion of a paired flavor solution in the absence of drug. Moreover, alterations in ambient temperature did not appear to influence conditioned taste aversion by changing ethanol pharmacokinetics. Finally, high and low ambient temperature did not affect development of taste aversion conditioned by lithium chloride or morphine sulfate. The overall pattern of data presented by these experiments supports the hypothesis that ambient-temperature influences strength of ethanol-induced conditioned taste aversion by altering the hypothermic response to ethanol. More generally, these data support the suggestion that body temperature change induced by ethanol is related to ethanol's aversive motivational effects and may be involved in modulating ethanol intake.

Flavor preference conditioning by oral self-administration of ethanol

“…Measurement of body temperature changes during oral self-administration indicated a negligible difference in body temperature (~0.1°C) between CS+ and CS-trials. Given previous findings suggesting a positive relationship between strength of conditioned flavor aversion and magnitude of ethanol-induced hypothermia (Cunningham et al 1988(Cunningham et al , 1992Cunningham and Niehus 1989), the absence of hypothermia in the present studies may have contributed importantly to the ability to obtain conditioned flavor preference rather than conditioned flavor aversion.…”

Differential Expression of Ethanol‐Induced Hypothermia in Adolescent and Adult Rats Induced by Pretest Familiarization to the Handling/Injection Procedure

“…Prior work has indicated that the hypothermic effects of ethanol may be aversive, with animals showing the greatest hypothermic reactions to ethanol also showing greater ethanol-induced taste aversions (Cunningham et al, 1992). Indeed, findings that handling prevented the formation of ethanol-induced conditioned place aversions in mice while having no impact on conditioned place preference (Bechtholt et al, 2004) were reminiscent of data from Experiment 2b showing a handling-associated attenuation in ethanol's hypothermic effects in adult rats.…”

Chronic systemic IL-1β exacerbates central neuroinflammation independently of the blood–brain barrier integrity

“…Peripheral cytokines, considered the main messengers of immune-brain signaling, exert their action through different pathways: permeable areas of the BBB, specific transporters, via endothelial cells (Bebo and Linthicum, 1995;Cunningham et al, 1992;Ericsson et al, 1995;Konsman et al, 2004;Vallieres and Rivest, 1999; Van Dam et al, 1996), through peripheral nerves, or a combination of these routes (Banks et al, 1995).…”