Continued Development and Unconditioned Stimulus Characterization of Selectively Bred Lines of Taste Aversion Prone and Resistant Rats

Abstract

This report updates the bidirectional selective breeding of taste aversion (TA) prone (TAP) and TA resistant (TAR) rat lines from the 8th through the 22nd generations. A palatable saccharin solution and the aversive consequences of a cyclophosphamide injection are the respective conditioned stimulus (CS) and unconditioned stimulus (US) of line development. Nonsibling matings within each of the two extremes of TA conditionability have produced TAP and TAR lines having markedly different TA propensities. As previously reported, the substitution of a rotational (i.e., motion sickness) US for cyclophosphamide during TA conditioning also produced characteristic line differences in conditioned taste aversion acquisition. The present report extends the effective line separating USs to include injections of lithium chloride, emetine hydrochloride, and EtOH. A range of EtOH dose levels produced dose-dependent TAs within TAP rats but failed to induce TAs in TAR rats. Following the conclusion of TA testing, the administration of a hypnotic EtOH dose produced equivalent loss of righting capability and equivalent hypothermia in both TAP and TAR rats. The line differences in EtOH induced TA conditionability therefore do not reflect general line differences in EtOH sensitivity. The lines may be useful within studies of biological bases of TA conditionability and animal analog studies of prevention and treatment of alcohol dependence.

High??? and Low???Alcohol-Preferring Mice Show Differences in Conditioned Taste Aversion to Alcohol

“…This hypothesis is supported by results of studies that have shown rats selectively bred for high CTA (taste aversion-prone rats) to the emetic agent, cyclophosphamide, demonstrate greater CTA to a wide variety of pharmacological agents, including alcohol (Elkins et al, 1992), and demonstrate decreased consumption and preference for alcohol than do their counterparts selectively bred for low CTA (taste aversionresistant rats) (Orr et al, 1997). This hypothesis is supported by results of studies that have shown rats selectively bred for high CTA (taste aversion-prone rats) to the emetic agent, cyclophosphamide, demonstrate greater CTA to a wide variety of pharmacological agents, including alcohol (Elkins et al, 1992), and demonstrate decreased consumption and preference for alcohol than do their counterparts selectively bred for low CTA (taste aversionresistant rats) (Orr et al, 1997).…”

Rat animal models for screening medications to treat alcohol use disorders

“…The High Saccharin Consumption (HiS) and Low Saccharin Consumption (LoS) Rats were selected for different propensities to consume a sweet, saccharin solution with the former consuming significantly more ethanol than the latter (c.f., Carroll et al, 2008). The Taste Aversion Prone (TAP) and Taste Aversion Resistant (TAR) rats were bidirectionally selected for cyclophosphamide conditioned taste aversion (CTA) to a saccharin solution, with the latter showing lower ethanol-induced CTA and greater ethanol intake than the former (e.g., Elkins et al, 1992; Orr et al, 2004). The Swim Test Susceptible (SUS) and Swim Test Resistant (RES) rats were bidirectionally selected for decreased swimming (SUS) activity when the test was preceded by a stressor, with the latter showing greater ethanol intake than the former (e.g., Weiss et al, 2008).…”

Cocaine‐Induced Expression Differences in PSD‐95/SAP‐90‐Associated Protein 4 and in Ca2+/Calmodulin‐Dependent Protein Kinase Subunits in Amygdalae of Taste Aversion‐Prone and Taste Aversion‐Resistant Rats

“…Taste aversion (TA)‐prone (TAP) and TA‐resistant (TAR) rats were selectively bred from a parental stock of Sprague Dawley‐derived rats 1. During the standard TA conditioning, ingestion of a novel 0.1% saccharin solution‐conditioned stimulus (CS) was paired with an injection of cyclophosphamide, an emetic class agent‐unconditioned stimulus (US).…”