Behavioral and biological markers for predicting compulsive-like drinking in schedule-induced polydipsia

Publication date: Available online 30 March 2019Source: Progress in Neuro-Psychopharmacology and Biological PsychiatryAuthor(s): A. Merchán, A. Sánchez-Kuhn, A. Prados-Pardo, B. Gago, F. Sánchez-Santed, M. Moreno, P. FloresAbstractSchedule-induced polydipsia (SIP), characterized by the development of persistent and excessive drinking under intermittent food-reinforcement schedules, is an animal model of compulsive behavior that can differentiate two populations: high drinkers (HD) and low drinkers (LD). The aim of the present study was to identify behavioral and biological markers to predict the vulnerability to developing compulsive-like drinking in SIP. Adult male Wistar rats were first trained in a spatial-discrimination serial reversal-learning task and in a reinforcer devaluation task to measure behavioral flexibility and habit formation, respectively. Subsequently, the rats were tested using the SIP protocol and identified as HD or LD based on their drinking rates. The performance of HD and LD rats in the two previous tasks was then analyzed. Before and after SIP exposure, blood glucose and plasma corticosterone (CORT) levels were measured. Additionally, serum electrolyte levels, including sodium, potassium, and chloride, were analyzed after SIP. HD rats showed higher behavioral inflexibility by exhibiting increased perseverative responses in the reversal-learning task and insensitivity to reinforcer devaluation during extinction under selective satiation. After SIP ...
Source: Progress in Neuro Psychopharmacology and Biological Psychiatry - Category: Psychiatry Source Type: research