Effects of concurrent access to multiple ethanol concentrations and repeated deprivations on alcohol intake of high-alcohol-drinking (HAD) rats.

High-alcohol-drinking rats, given access to 10% ethanol, expressed an alcohol deprivation effect (ADE) only after multiple deprivations. In alcohol-preferring (P) rats, concurrent access to multiple ethanol concentrations combined with repeated cycles of EtOH access and deprivation produced excessive ethanol drinking. The current study was undertaken to examine the effects of repeated alcohol deprivations with concurrent access to multiple concentrations of ethanol on ethanol intake of HAD replicate lines of rats.

Effects of alcohol and saccharin deprivations on concurrent ethanol and saccharin operant self-administration by alcohol-preferring (P) rats.

Consumption of sweet solutions has been associated with a reduction in withdrawal symptoms and alcohol craving in humans. The objective of the present study was to determine the effects of ethanol and saccharin (SACC) deprivations on operant oral self-administration. Alcohol-preferring (P) rats were allowed to lever press concurrently self-administer ethanol (15% vol/vol) and SACC (0.

Effects of multiple alcohol deprivations on operant ethanol self-administration by high-alcohol-drinking replicate rat lines.

Previously, we reported that the expression of an alcohol deprivation effect (ADE) under 24-h free-choice alcohol-drinking access in high-alcohol-drinking (HAD) replicate lines of rats is dependent upon repeated cycles of alcohol access and forced abstinence. In the present study, operant techniques (including progressive ratio measures) were used to examine the effects of initial deprivation length and number of deprivation cycles on the magnitude and duration of the ADE in HAD rats to test the hypothesis that repeated deprivations increase the reinforcing effects of ethanol. Adult male HAD-1 and HAD-2 rats were trained in two-lever operant chambers to concurrently self-administer 15% ethanol (v/v) on a fixed-ratio (FR)-5 schedule and water on an FR-1 schedule of reinforcement in daily 1-h sessions.

Intracranial self-administration of cocaine within the posterior ventral tegmental area of Wistar rats: evidence for involvement of serotonin-3 receptors and dopamine neurons.

The rewarding properties of cocaine have been postulated to be regulated, in part, by the mesolimbic dopamine (DA) system. The present study assessed whether adult female Wistar rats would self-administer cocaine directly into the ventral tegmental area (VTA). Following guide cannulae surgery aimed at either the posterior or anterior VTA, subjects were placed in an operant box equipped with an active lever that caused the delivery of the infusate and an inactive lever that did not.

Comparison of intracranial self-administration of ethanol within the posterior ventral tegmental area between alcohol-preferring and Wistar rats.

Background: A previous study indicated that selectively bred alcohol-preferring (P) rats self-administered ethanol (EtOH) directly into the ventral tegmental area (VTA), whereas the alcohol-nonpreferring line did not. Wistar rats will also self-administer EtOH directly into the posterior VTA. Because Wistar rats also have a low preference for EtOH solutions but self-inject EtOH into the VTA, this study was undertaken to test the hypothesis that there is an association between EtOH preference and sensitivity of the VTA to the reinforcing effects of EtOH.

Intracranial self-administration of ethanol within the ventral tegmental area of male Wistar rats: evidence for involvement of dopamine neurons.

Previous work from our laboratory indicated that female Wistar rats will self-administer ethanol (EtOH) directly into the posterior ventral tegmental area (VTA). These results suggested that VTA dopamine (DA) neurons might be involved in mediating the reinforcing actions of EtOH within this region. The objectives of this study were to determine (1) the dose-response effects for the self-administration of EtOH into the VTA of male Wistar rats, and (2) the involvement of VTA DA neurons in the reinforcing actions of EtOH within the VTA.

Effects of repeated alcohol deprivations on operant ethanol self-administration by alcohol-preferring (P) rats.

We reported that repeated alcohol deprivations prolonged the expression of an alcohol-deprivation effect (ADE) under 24-h free-choice alcohol-drinking access and that the duration of the initial deprivation period had a positive effect of prolonging the duration of the ADE. In the present study, operant techniques (including progressive ratio measures) were used to examine the effects of initial deprivation length and number of deprivation cycles on the magnitude and duration of the ADE in alcohol-preferring (P) rats to test the hypothesis that repeated deprivations can increase the reinforcing effects of ethanol (ETOH). Adult male P rats were trained in two-lever operant chambers to self-administer 15% ETOH (v/v) on a fixed-ratio 5 (FR-5) and water on a FR-1 schedule of reinforcement in daily 1-h sessions.

Effects of concurrent access to a single concentration or multiple concentrations of ethanol on the intake of ethanol by male and female periadolescent alcohol-preferring (P) rats.

The objectives of this study were to assess the effects of access to different concentrations of ethanol and sex of the animal on ethanol consumption during periadolescence [postnatal days (PNDs) 30-60] in alcohol-preferring (P) rats. On PND 28, female and male P pups were single housed in hanging stainless steel cages with ad libitum access to water and food. Beginning on PND 30, the rats were also given access to either a single concentration [15% volume/volume (vol.

Effects of ethanol exposure on subsequent acquisition and extinction of ethanol self-administration and expression of alcohol-seeking behavior in adult alcohol-preferring (P) rats: II. Adult exposure.

Background: In a preceding study, we reported that ethanol (EtOH) consumption during periadolescence in alcohol-preferring (P) rats produced significant effects on the acquisition, extinction, Pavlovian spontaneous recovery (PSR), and reacquisition of operant self-administration of EtOH. The objective of the present study was to determine if EtOH consumption during adulthood produced similar effects on subsequent operant behaviors.

Methods: Adult female P rats (>135 days of age) were given 24 hr free-choice access to 15% EtOH for 30 days or were similarly housed and received water only.

Effects of ethanol exposure on subsequent acquisition and extinction of ethanol self-administration and expression of alcohol-seeking behavior in adult alcohol-preferring (P) rats: I. Periadolescent exposure.

Background: The current study examined the effects of ethanol (EtOH) drinking during periadolescence on the subsequent acquisition and extinction of operant self-administration of EtOH and expression of alcohol-seeking behavior in adult alcohol-preferring (P) rats to test the hypothesis that alcohol drinking during periadolescence produces enduring alterations that enhance the reinforcing properties of EtOH.

Methods: Periadolescent female P rats were given 24 hr free-choice access to 15% (v/v) EtOH starting at postnatal day (PND) 30 and ending on PND 60 or were similarly housed and received water only. On PND 75, without any prior training, periadolescent alcohol-drinking and periadolescent alcohol-naïve rats were placed in standard two-lever (15% EtOH and water) chambers to examine acquisition of EtOH self-administration with a fixed ratio (FR) 1 schedule of reinforcement.