Alcohol-Preferring P Rats Emit Spontaneous 22-28 kHz Ultrasonic Vocalizations that are Altered by Acute and Chronic Alcohol Experience

作者：Reno James M; Thakore Neha; Gonzales Rueben; Schallert Timothy; Bell Richard L; Maddox W Todd; Duvauchelle Christine L^*

来源：Alcoholism: Clinical and Experimental Research , 2015, 39(5): 843-852.

DOI：10.1111/acer.12706

• WAAVES
• Drinking-In-The-Dark
• Emotional Status
• Negative Affect
• Excessive Alcohol Intake

BackgroundEmotional states are often thought to drive excessive alcohol intake and influence the development of alcohol use disorders. To gain insight into affective properties associated with excessive alcohol intake, we utilized ultrasonic vocalization (USV) detection and analyses to characterize the emotional phenotype of selectively bred alcohol-preferring (P) rats; an established animal model of excessive alcohol intake. USVs emitted by rodents have been convincingly associated with positive (50-55 kHz frequency-modulated [FM]) and negative (22-28kHz) affective states. Therefore, we hypothesized that 50-55 and 22-28kHz USV emission patterns in P rats would reveal a unique emotional phenotype sensitive to alcohol experience.
Methods50-55kHz FM and 22-28kHz USVs elicited from male P rats were assessed during access to water, 15 and 30% EtOH (v/v). Ethanol (EtOH; n=12) or water only (Control; n=4) across 8weeks of daily drinking-in-the-dark (DID) sessions.
ResultsSpontaneous 22-28kHz USVs are emitted by alcohol-naive P rats and are enhanced by alcohol experience. During DID sessions when alcohol was not available (e.g., EtOH OFF intervals), significantly more 22-28kHz than 50-55kHz USVs were elicited, while significantly more 50-55kHz FM than 22-28kHz USVs were emitted when alcohol was available (e.g., EtOH ON intervals). In addition, USV acoustic property analyses revealed chronic effects of alcohol experience on 22-28kHz USV mean frequency, indicative of lasting alcohol-mediated alterations to neural substrates underlying emotional response.
ConclusionsOur findings demonstrate that acute and chronic effects of alcohol exposure are reflected in changes in 22-28 and 50-55kHz FM USV counts and acoustic patterns. These data support the notion that initiation and maintenance of alcohol intake in P rats may be due to a unique, alcohol-responsive emotional phenotype and further suggest that spontaneous 22-28kHz USVs serve as behavioral markers for excessive drinking vulnerability.

• 出版日期2015-5